3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes

<!DOCTYPE html> <html lang="en" xmlns:og="http://ogp.me/ns#" xmlns:fb="https://www.facebook.com/2008/fbml"> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> <meta content="mdpi" name="sso-service" /> <meta content="width=device-width, initial-scale=1.0" name="viewport" /> <title>3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes</title><link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/font-awesome.min.css?eb190a3a77e5e1ee?1739771134"> <link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/jquery.multiselect.css?f56c135cbf4d1483?1739771134"> <link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/chosen.min.css?d7ca5ca9441ef9e1?1739771134"> <link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/main2.css?6398b1425402cd8f?1739771134"> <link rel="mask-icon" href="https://pub.mdpi-res.com/img/mask-icon-128.svg?c1c7eca266cd7013?1739771134" color="#4f5671"> <link rel="apple-touch-icon" sizes="180x180" href="https://pub.mdpi-res.com/icon/apple-touch-icon-180x180.png?1739771134"> <link rel="apple-touch-icon" sizes="152x152" href="https://pub.mdpi-res.com/icon/apple-touch-icon-152x152.png?1739771134"> <link rel="apple-touch-icon" sizes="144x144" href="https://pub.mdpi-res.com/icon/apple-touch-icon-144x144.png?1739771134"> <link rel="apple-touch-icon" sizes="120x120" href="https://pub.mdpi-res.com/icon/apple-touch-icon-120x120.png?1739771134"> <link rel="apple-touch-icon" sizes="114x114" href="https://pub.mdpi-res.com/icon/apple-touch-icon-114x114.png?1739771134"> <link rel="apple-touch-icon" sizes="76x76" href="https://pub.mdpi-res.com/icon/apple-touch-icon-76x76.png?1739771134"> <link rel="apple-touch-icon" sizes="72x72" href="https://pub.mdpi-res.com/icon/apple-touch-icon-72x72.png?1739771134"> <link rel="apple-touch-icon" sizes="57x57" href="https://pub.mdpi-res.com/icon/apple-touch-icon-57x57.png?1739771134"> <link rel="apple-touch-icon" href="https://pub.mdpi-res.com/icon/apple-touch-icon-57x57.png?1739771134"> <link rel="apple-touch-icon-precomposed" href="https://pub.mdpi-res.com/icon/apple-touch-icon-57x57.png?1739771134"> <link rel="manifest" href="/manifest.json"> <meta name="theme-color" content="#ffffff"> <meta name="application-name" content=" "/> <link rel="apple-touch-startup-image" href="https://pub.mdpi-res.com/img/journals/jfb-logo-sq.png?8600e93ff98dbf14"> <link rel="apple-touch-icon" href="https://pub.mdpi-res.com/img/journals/jfb-logo-sq.png?8600e93ff98dbf14"> <meta name="msapplication-TileImage" content="https://pub.mdpi-res.com/img/journals/jfb-logo-sq.png?8600e93ff98dbf14"> <link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/jquery-ui-1.10.4.custom.min.css?80647d88647bf347?1739771134"> <link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/magnific-popup.min.css?04d343e036f8eecd?1739771134"> <link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/xml2html/article-html.css?230b005b39af4260?1739771134"> <style> h2, #abstract .related_suggestion_title { } .batch_articles a { color: #000; } a, .batch_articles .authors a, a:focus, a:hover, a:active, .batch_articles a:focus, .batch_articles a:hover, li.side-menu-li a { } span.label a { color: #fff; } #main-content a.title-link:hover, #main-content a.title-link:focus, #main-content div.generic-item a.title-link:hover, #main-content div.generic-item a.title-link:focus { } #main-content #middle-column .generic-item.article-item a.title-link:hover, #main-content #middle-column .generic-item.article-item a.title-link:focus { } .art-authors a.toEncode { color: #333; font-weight: 700; } #main-content #middle-column ul li::before { } .accordion-navigation.active a.accordion__title, .accordion-navigation.active a.accordion__title::after { } .accordion-navigation li:hover::before, .accordion-navigation li:hover a, .accordion-navigation li:focus a { } .relative-size-container .relative-size-image .relative-size { } .middle-column__help__fixed a:hover i, } input[type="checkbox"]:checked:after { } input[type="checkbox"]:not(:disabled):hover:before { } #main-content .bolded-text { } #main-content .hypothesis-count-container { } #main-content .hypothesis-count-container:before { } .full-size-menu ul li.menu-item .dropdown-wrapper { } .full-size-menu ul li.menu-item > a.open::after { } #title-story .title-story-orbit .orbit-caption { #background: url('/img/design/000000_background.png') !important; background: url('/img/design/ffffff_background.png') !important; color: rgb(51, 51, 51) !important; } #main-content .content__container__orbit { background-color: #000 !important; } #main-content .content__container__journal { color: #fff; } .html-article-menu .row span { } .html-article-menu .row span.active { } .accordion-navigation__journal .side-menu-li.active::before, .accordion-navigation__journal .side-menu-li.active a { color: rgba(0,95,84,0.75) !important; font-weight: 700; } .accordion-navigation__journal .side-menu-li:hover::before , .accordion-navigation__journal .side-menu-li:hover a { color: rgba(0,95,84,0.75) !important; } .side-menu-ul li.active a, .side-menu-ul li.active, .side-menu-ul li.active::before { color: rgba(0,95,84,0.75) !important; } .side-menu-ul li.active a { } .result-selected, .active-result.highlighted, .active-result:hover, .result-selected, .active-result.highlighted, .active-result:focus { } .search-container.search-container__default-scheme { } nav.tab-bar .open-small-search.active:after { } .search-container.search-container__default-scheme .custom-accordion-for-small-screen-link::after { color: #fff; } @media only screen and (max-width: 50em) { #main-content .content__container.journal-info { color: #fff; } #main-content .content__container.journal-info a { color: #fff; } } .button.button--color { } .button.button--color:hover, .button.button--color:focus { } .button.button--color-journal { position: relative; background-color: rgba(0,95,84,0.75); border-color: #fff; color: #fff !important; } .button.button--color-journal:hover::before { content: ''; position: absolute; top: 0; left: 0; height: 100%; width: 100%; background-color: #ffffff; opacity: 0.2; } .button.button--color-journal:visited, .button.button--color-journal:hover, .button.button--color-journal:focus { background-color: rgba(0,95,84,0.75); border-color: #fff; color: #fff !important; } .button.button--color path { } .button.button--color:hover path { fill: #fff; } #main-content #search-refinements .ui-slider-horizontal .ui-slider-range { } .breadcrumb__element:last-of-type a { } #main-header { } #full-size-menu .top-bar, #full-size-menu li.menu-item span.user-email { } .top-bar-section li:not(.has-form) a:not(.button) { } #full-size-menu li.menu-item .dropdown-wrapper li a:hover { } #full-size-menu li.menu-item a:hover, #full-size-menu li.menu.item a:focus, nav.tab-bar a:hover { } #full-size-menu li.menu.item a:active, #full-size-menu li.menu.item a.active { } #full-size-menu li.menu-item a.open-mega-menu.active, #full-size-menu li.menu-item div.mega-menu, a.open-mega-menu.active { } #full-size-menu li.menu-item div.mega-menu li, #full-size-menu li.menu-item div.mega-menu a { border-color: #9a9a9a; } div.type-section h2 { font-size: 20px; line-height: 26px; font-weight: 300; } div.type-section h3 { margin-left: 15px; margin-bottom: 0px; font-weight: 300; } .journal-tabs .tab-title.active a { } </style> <link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/slick.css?f38b2db10e01b157?1739771134"> <meta name="title" content="3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes"> <meta name="description" content="We describe the development of a bioink to bioprint human induced pluripotent stem cells (hiPSCs) for possible cardiac tissue engineering using a gelatin methacrylate (GelMA)-based hydrogel. While previous studies have shown that GelMA at a low concentration (5% w/v) allows for the growth of diverse cells, its 3D printability has been found to be limited by its low viscosity. To overcome that drawback, making the hydrogel both compatible with hiPSCs and 3D-printable, we developed an extrudable GelMA-based bioink by adding xanthan gum (XG). The GelMA-XG composite hydrogel had an elastic modulus (~9 kPa) comparable to that of cardiac tissue, and enabled 3D printing with high values of printing accuracy (83%) and printability (0.98). Tests with hiPSCs showed the hydrogel’s ability to promote their proliferation within both 2D and 3D cell cultures. The tests also showed that hiPSCs inside hemispheres of the hydrogel were able to differentiate into cardiomyocytes, capable of spontaneous contractions (average frequency of ~0.5 Hz and amplitude of ~2%). Furthermore, bioprinting tests proved the possibility of fabricating 3D constructs of the hiPSC-laden hydrogel, with well-defined line widths (~800 μm)." > <link rel="image_src" href="https://pub.mdpi-res.com/img/journals/jfb-logo.png?8600e93ff98dbf14" > <meta name="dc.title" content="3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes"> <meta name="dc.creator" content="Virginia Deidda"> <meta name="dc.creator" content="Isabel Ventisette"> <meta name="dc.creator" content="Marianna Langione"> <meta name="dc.creator" content="Lucrezia Giammarino"> <meta name="dc.creator" content="Josè Manuel Pioner"> <meta name="dc.creator" content="Caterina Credi"> <meta name="dc.creator" content="Federico Carpi"> <meta name="dc.type" content="Article"> <meta name="dc.source" content="Journal of Functional Biomaterials 2024, Vol. 15, Page 297"> <meta name="dc.date" content="2024-10-05"> <meta name ="dc.identifier" content="10.3390/jfb15100297"> <meta name="dc.publisher" content="Multidisciplinary Digital Publishing Institute"> <meta name="dc.rights" content="http://creativecommons.org/licenses/by/3.0/"> <meta name="dc.format" content="application/pdf" > <meta name="dc.language" content="en" > <meta name="dc.description" content="We describe the development of a bioink to bioprint human induced pluripotent stem cells (hiPSCs) for possible cardiac tissue engineering using a gelatin methacrylate (GelMA)-based hydrogel. While previous studies have shown that GelMA at a low concentration (5% w/v) allows for the growth of diverse cells, its 3D printability has been found to be limited by its low viscosity. To overcome that drawback, making the hydrogel both compatible with hiPSCs and 3D-printable, we developed an extrudable GelMA-based bioink by adding xanthan gum (XG). The GelMA-XG composite hydrogel had an elastic modulus (~9 kPa) comparable to that of cardiac tissue, and enabled 3D printing with high values of printing accuracy (83%) and printability (0.98). Tests with hiPSCs showed the hydrogel’s ability to promote their proliferation within both 2D and 3D cell cultures. The tests also showed that hiPSCs inside hemispheres of the hydrogel were able to differentiate into cardiomyocytes, capable of spontaneous contractions (average frequency of ~0.5 Hz and amplitude of ~2%). Furthermore, bioprinting tests proved the possibility of fabricating 3D constructs of the hiPSC-laden hydrogel, with well-defined line widths (~800 μm)." > <meta name="dc.subject" content="3D bioprinting" > <meta name="dc.subject" content="hydrogel" > <meta name="dc.subject" content="HiPSCs" > <meta name="dc.subject" content="gelatin" > <meta name="dc.subject" content="GelMA" > <meta name="dc.subject" content="xanthan gum" > <meta name="dc.subject" content="cardiac" > <meta name="dc.subject" content="tissue engineering" > <meta name ="prism.issn" content="2079-4983"> <meta name ="prism.publicationName" content="Journal of Functional Biomaterials"> <meta name ="prism.publicationDate" content="2024-10-05"> <meta name ="prism.volume" content="15"> <meta name ="prism.number" content="10"> <meta name ="prism.section" content="Article" > <meta name ="prism.startingPage" content="297" > <meta name="citation_issn" content="2079-4983"> <meta name="citation_journal_title" content="Journal of Functional Biomaterials"> <meta name="citation_publisher" content="Multidisciplinary Digital Publishing Institute"> <meta name="citation_title" content="3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes"> <meta name="citation_publication_date" content="2024/10"> <meta name="citation_online_date" content="2024/10/05"> <meta name="citation_volume" content="15"> <meta name="citation_issue" content="10"> <meta name="citation_firstpage" content="297"> <meta name="citation_author" content="Deidda, Virginia"> <meta name="citation_author" content="Ventisette, Isabel"> <meta name="citation_author" content="Langione, Marianna"> <meta name="citation_author" content="Giammarino, Lucrezia"> <meta name="citation_author" content="Pioner, Josè Manuel"> <meta name="citation_author" content="Credi, Caterina"> <meta name="citation_author" content="Carpi, Federico"> <meta name="citation_doi" content="10.3390/jfb15100297"> <meta name="citation_id" content="mdpi-jfb15100297"> <meta name="citation_abstract_html_url" content="https://www.mdpi.com/2079-4983/15/10/297"> <meta name="citation_pdf_url" content="https://www.mdpi.com/2079-4983/15/10/297/pdf?version=1728118721"> <link rel="alternate" type="application/pdf" title="PDF Full-Text" href="https://www.mdpi.com/2079-4983/15/10/297/pdf?version=1728118721"> <meta name="fulltext_pdf" content="https://www.mdpi.com/2079-4983/15/10/297/pdf?version=1728118721"> <meta name="citation_fulltext_html_url" content="https://www.mdpi.com/2079-4983/15/10/297/htm"> <link rel="alternate" type="text/html" title="HTML Full-Text" href="https://www.mdpi.com/2079-4983/15/10/297/htm"> <meta name="fulltext_html" content="https://www.mdpi.com/2079-4983/15/10/297/htm"> <link rel="alternate" type="text/xml" title="XML Full-Text" href="https://www.mdpi.com/2079-4983/15/10/297/xml"> <meta name="fulltext_xml" content="https://www.mdpi.com/2079-4983/15/10/297/xml"> <meta name="citation_xml_url" content="https://www.mdpi.com/2079-4983/15/10/297/xml"> <meta name="twitter:card" content="summary" /> <meta name="twitter:site" content="@MDPIOpenAccess" /> <meta name="twitter:image" content="https://pub.mdpi-res.com/img/journals/jfb-logo-social.png?8600e93ff98dbf14" /> <meta property="fb:app_id" content="131189377574"/> <meta property="og:site_name" content="MDPI"/> <meta property="og:type" content="article"/> <meta property="og:url" content="https://www.mdpi.com/2079-4983/15/10/297" /> <meta property="og:title" content="3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes" /> <meta property="og:description" content="We describe the development of a bioink to bioprint human induced pluripotent stem cells (hiPSCs) for possible cardiac tissue engineering using a gelatin methacrylate (GelMA)-based hydrogel. While previous studies have shown that GelMA at a low concentration (5% w/v) allows for the growth of diverse cells, its 3D printability has been found to be limited by its low viscosity. To overcome that drawback, making the hydrogel both compatible with hiPSCs and 3D-printable, we developed an extrudable GelMA-based bioink by adding xanthan gum (XG). The GelMA-XG composite hydrogel had an elastic modulus (~9 kPa) comparable to that of cardiac tissue, and enabled 3D printing with high values of printing accuracy (83%) and printability (0.98). Tests with hiPSCs showed the hydrogel’s ability to promote their proliferation within both 2D and 3D cell cultures. The tests also showed that hiPSCs inside hemispheres of the hydrogel were able to differentiate into cardiomyocytes, capable of spontaneous contractions (average frequency of ~0.5 Hz and amplitude of ~2%). Furthermore, bioprinting tests proved the possibility of fabricating 3D constructs of the hiPSC-laden hydrogel, with well-defined line widths (~800 μm)." /> <meta property="og:image" content="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g001-550.jpg?1728118842" /> <link rel="alternate" type="application/rss+xml" title="MDPI Publishing - Latest articles" href="https://www.mdpi.com/rss"> <meta name="google-site-verification" content="PxTlsg7z2S00aHroktQd57fxygEjMiNHydKn3txhvwY"> <meta name="facebook-domain-verification" content="mcoq8dtq6sb2hf7z29j8w515jjoof7" /> <script id="Cookiebot" data-cfasync="false" src="https://consent.cookiebot.com/uc.js" data-cbid="51491ddd-fe7a-4425-ab39-69c78c55829f" type="text/javascript" async></script>  <script type="text/plain" data-cookieconsent="statistics"> (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start': new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0], j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src= 'https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f); })(window,document,'script','dataLayer','GTM-WPK7SW5'); </script> <script type="text/plain" data-cookieconsent="statistics"> _linkedin_partner_id = "2846186"; window._linkedin_data_partner_ids = window._linkedin_data_partner_ids || []; window._linkedin_data_partner_ids.push(_linkedin_partner_id); </script><script type="text/javascript"> (function(){var s = document.getElementsByTagName("script")[0]; var b = document.createElement("script"); b.type = "text/javascript";b.async = true; b.src = "https://snap.licdn.com/li.lms-analytics/insight.min.js"; s.parentNode.insertBefore(b, s);})(); </script> <script type="text/plain" data-cookieconsent="statistics" data-cfasync="false" src="//script.crazyegg.com/pages/scripts/0116/4951.js" async="async" ></script> </head> <body> <div class="direction direction_right" id="small_right" style="border-right-width: 0px; padding:0;"> <i class="fa fa-caret-right fa-2x"></i> </div> <div class="big_direction direction_right" id="big_right" style="border-right-width: 0px;"> <div style="text-align: right;"> Next Article in Journal<br> <div><a href="/2079-4983/15/10/298">Theoretical Model for In Vivo Induction of Chemotherapy Sensitization Using miRNA Packaged in Distinct Layered Liposomes</a></div> </div> </div> <div class="direction" id="small_left" style="border-left-width: 0px"> <i class="fa fa-caret-left fa-2x"></i> </div> <div class="big_direction" id="big_left" style="border-left-width: 0px;"> <div> Previous Article in Journal<br> <div><a href="/2079-4983/15/10/296">PMA-Zeolite: Chemistry and Diverse Medical Applications</a></div> </div> </div> <div style="clear: both;"></div> <div id="menuModal" class="reveal-modal reveal-modal-new reveal-modal-menu" aria-hidden="true" data-reveal role="dialog"> <div class="menu-container"> <div class="UI_NavMenu"> <div class="content__container " > <div class="custom-accordion-for-small-screen-link " > <h2>Journals</h2> </div> <div class="target-item custom-accordion-for-small-screen-content show-for-medium-up"> <div class="menu-container__links"> <div style="width: 100%; float: left;"> <a href="/about/journals">Active Journals</a> <a href="/about/journalfinder">Find a Journal</a> <a href="/about/journals/proposal">Journal Proposal</a> <a href="/about/proceedings">Proceedings Series</a> </div> </div> </div> </div> <a href="/topics"> <h2>Topics</h2> </a> <div class="content__container " > <div class="custom-accordion-for-small-screen-link " > <h2>Information</h2> </div> <div class="target-item custom-accordion-for-small-screen-content show-for-medium-up"> <div class="menu-container__links"> <div style="width: 100%; max-width: 200px; float: left;"> <a href="/authors">For Authors</a> <a href="/reviewers">For Reviewers</a> <a href="/editors">For Editors</a> <a href="/librarians">For Librarians</a> <a href="/publishing_services">For Publishers</a> <a href="/societies">For Societies</a> <a href="/conference_organizers">For Conference Organizers</a> </div> <div style="width: 100%; max-width: 250px; float: left;"> <a href="/openaccess">Open Access Policy</a> <a href="/ioap">Institutional Open Access Program</a> <a href="/special_issues_guidelines">Special Issues Guidelines</a> <a href="/editorial_process">Editorial Process</a> <a href="/ethics">Research and Publication Ethics</a> <a href="/apc">Article Processing Charges</a> <a href="/awards">Awards</a> <a href="/testimonials">Testimonials</a> </div> </div> </div> </div> <a href="/authors/english"> <h2>Author Services</h2> </a> <div class="content__container " > <div class="custom-accordion-for-small-screen-link " > <h2>Initiatives</h2> </div> <div class="target-item custom-accordion-for-small-screen-content show-for-medium-up"> <div class="menu-container__links"> <div style="width: 100%; float: left;"> <a href="https://sciforum.net" target="_blank" rel="noopener noreferrer">Sciforum</a> <a href="https://www.mdpi.com/books" target="_blank" rel="noopener noreferrer">MDPI Books</a> <a href="https://www.preprints.org" target="_blank" rel="noopener noreferrer">Preprints.org</a> <a href="https://www.scilit.com" target="_blank" rel="noopener noreferrer">Scilit</a> <a href="https://sciprofiles.com" target="_blank" rel="noopener noreferrer">SciProfiles</a> <a href="https://encyclopedia.pub" target="_blank" rel="noopener noreferrer">Encyclopedia</a> <a href="https://jams.pub" target="_blank" rel="noopener noreferrer">JAMS</a> <a href="/about/proceedings">Proceedings Series</a> </div> </div> </div> </div> <div class="content__container " > <div class="custom-accordion-for-small-screen-link " > <h2>About</h2> </div> <div class="target-item custom-accordion-for-small-screen-content show-for-medium-up"> <div class="menu-container__links"> <div style="width: 100%; float: left;"> <a href="/about">Overview</a> <a href="/about/contact">Contact</a> <a href="https://careers.mdpi.com" target="_blank" rel="noopener noreferrer">Careers</a> <a href="/about/announcements">News</a> <a href="/about/press">Press</a> <a href="http://blog.mdpi.com/" target="_blank" rel="noopener noreferrer">Blog</a> </div> </div> </div> </div> </div> <div class="menu-container__buttons"> <a class="button UA_SignInUpButton" href="/user/login">Sign In / Sign Up</a> </div> </div> </div> <div id="captchaModal" class="reveal-modal reveal-modal-new reveal-modal-new--small" data-reveal aria-label="Captcha" aria-hidden="true" role="dialog"></div> <div id="actionDisabledModal" class="reveal-modal" data-reveal aria-labelledby="actionDisableModalTitle" aria-hidden="true" role="dialog" style="width: 300px;"> <h2 id="actionDisableModalTitle">Notice</h2> <form action="/email/captcha" method="post" id="emailCaptchaForm"> <div class="row"> <div id="js-action-disabled-modal-text" class="small-12 columns"> </div> <div id="js-action-disabled-modal-submit" class="small-12 columns" style="margin-top: 10px; display: none;"> You can make submissions to other journals <a href="https://susy.mdpi.com/user/manuscripts/upload">here</a>. </div> </div> </form> <a class="close-reveal-modal" aria-label="Close"> <i class="material-icons">clear</i> </a> </div> <div id="rssNotificationModal" class="reveal-modal reveal-modal-new" data-reveal aria-labelledby="rssNotificationModalTitle" aria-hidden="true" role="dialog"> <div class="row"> <div class="small-12 columns"> <h2 id="rssNotificationModalTitle">Notice</h2> <p> You are accessing a machine-readable page. In order to be human-readable, please install an RSS reader. </p> </div> </div> <div class="row"> <div class="small-12 columns"> <a class="button button--color js-rss-notification-confirm">Continue</a> <a class="button button--grey" onclick="$(this).closest('.reveal-modal').find('.close-reveal-modal').click(); return false;">Cancel</a> </div> </div> <a class="close-reveal-modal" aria-label="Close"> <i class="material-icons">clear</i> </a> </div> <div id="drop-article-label-openaccess" class="f-dropdown medium" data-dropdown-content aria-hidden="true" tabindex="-1"> <p> All articles published by MDPI are made immediately available worldwide under an open access license. No special permission is required to reuse all or part of the article published by MDPI, including figures and tables. For articles published under an open access Creative Common CC BY license, any part of the article may be reused without permission provided that the original article is clearly cited. For more information, please refer to <a href="https://www.mdpi.com/openaccess">https://www.mdpi.com/openaccess</a>. </p> </div> <div id="drop-article-label-feature" class="f-dropdown medium" data-dropdown-content aria-hidden="true" tabindex="-1"> <p> Feature papers represent the most advanced research with significant potential for high impact in the field. A Feature Paper should be a substantial original Article that involves several techniques or approaches, provides an outlook for future research directions and describes possible research applications. </p> <p> Feature papers are submitted upon individual invitation or recommendation by the scientific editors and must receive positive feedback from the reviewers. </p> </div> <div id="drop-article-label-choice" class="f-dropdown medium" data-dropdown-content aria-hidden="true" tabindex="-1"> <p> Editor’s Choice articles are based on recommendations by the scientific editors of MDPI journals from around the world. Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to readers, or important in the respective research area. The aim is to provide a snapshot of some of the most exciting work published in the various research areas of the journal. <div style="margin-top: -10px;"> <div id="drop-article-label-choice-journal-link" style="display: none; margin-top: -10px; padding-top: 10px;"> </div> </div> </p> </div> <div id="drop-article-label-resubmission" class="f-dropdown medium" data-dropdown-content aria-hidden="true" tabindex="-1"> <p> Original Submission Date Received: <span id="drop-article-label-resubmission-date"></span>. </p> </div> <div id="container"> <noscript> <div id="no-javascript"> You seem to have javascript disabled. Please note that many of the page functionalities won't work as expected without javascript enabled. </div> </noscript> <div class="fixed"> <nav class="tab-bar show-for-medium-down"> <div class="row full-width collapse"> <div class="medium-3 small-4 columns"> <a href="/"> <img class="full-size-menu__mdpi-logo" src="https://pub.mdpi-res.com/img/design/mdpi-pub-logo-black-small1.svg?da3a8dcae975a41c?1739771134" style="width: 64px;" title="MDPI Open Access Journals"> </a> </div> <div class="medium-3 small-4 columns right-aligned"> <div class="show-for-medium-down"> <a href="#" style="display: none;"> <i class="material-icons" onclick="$('#menuModal').foundation('reveal', 'close'); return false;">clear</i> </a> <a class="js-toggle-desktop-layout-link" title="Toggle desktop layout" style="display: none;" href="/toggle_desktop_layout_cookie"> <i class="material-icons">zoom_out_map</i> </a> <a href="#" class="js-open-small-search open-small-search"> <i class="material-icons show-for-small only">search</i> </a> <a title="MDPI main page" class="js-open-menu" data-reveal-id="menuModal" href="#"> <i class="material-icons">menu</i> </a> </div> </div> </div> </nav> </div> <section class="main-section"> <header> <div class="full-size-menu show-for-large-up"> <div class="row full-width"> <div class="large-1 columns"> <a href="/"> <img class="full-size-menu__mdpi-logo" src="https://pub.mdpi-res.com/img/design/mdpi-pub-logo-black-small1.svg?da3a8dcae975a41c?1739771134" title="MDPI Open Access Journals"> </a> </div> <div class="large-8 columns text-right UI_NavMenu"> <ul> <li class="menu-item"> <a href="/about/journals" data-dropdown="journals-dropdown" aria-controls="journals-dropdown" aria-expanded="false" data-options="is_hover: true; hover_timeout: 200">Journals</a> <ul id="journals-dropdown" class="f-dropdown dropdown-wrapper dropdown-wrapper__small" data-dropdown-content aria-hidden="true" tabindex="-1"> <li> <div class="row"> <div class="small-12 columns"> <ul> <li> <a href="/about/journals"> Active Journals </a> </li> <li> <a href="/about/journalfinder"> Find a Journal </a> </li> <li> <a href="/about/journals/proposal"> Journal Proposal </a> </li> <li> <a href="/about/proceedings"> Proceedings Series </a> </li> </ul> </div> </div> </li> </ul> </li> <li class="menu-item"> <a href="/topics">Topics</a> </li> <li class="menu-item"> <a href="/authors" data-dropdown="information-dropdown" aria-controls="information-dropdown" aria-expanded="false" data-options="is_hover:true; hover_timeout:200">Information</a> <ul id="information-dropdown" class="f-dropdown dropdown-wrapper" data-dropdown-content aria-hidden="true" tabindex="-1"> <li> <div class="row"> <div class="small-5 columns right-border"> <ul> <li> <a href="/authors">For Authors</a> </li> <li> <a href="/reviewers">For Reviewers</a> </li> <li> <a href="/editors">For Editors</a> </li> <li> <a href="/librarians">For Librarians</a> </li> <li> <a href="/publishing_services">For Publishers</a> </li> <li> <a href="/societies">For Societies</a> </li> <li> <a href="/conference_organizers">For Conference Organizers</a> </li> </ul> </div> <div class="small-7 columns"> <ul> <li> <a href="/openaccess">Open Access Policy</a> </li> <li> <a href="/ioap">Institutional Open Access Program</a> </li> <li> <a href="/special_issues_guidelines">Special Issues Guidelines</a> </li> <li> <a href="/editorial_process">Editorial Process</a> </li> <li> <a href="/ethics">Research and Publication Ethics</a> </li> <li> <a href="/apc">Article Processing Charges</a> </li> <li> <a href="/awards">Awards</a> </li> <li> <a href="/testimonials">Testimonials</a> </li> </ul> </div> </div> </li> </ul> </li> <li class="menu-item"> <a href="/authors/english">Author Services</a> </li> <li class="menu-item"> <a href="/about/initiatives" data-dropdown="initiatives-dropdown" aria-controls="initiatives-dropdown" aria-expanded="false" data-options="is_hover: true; hover_timeout: 200">Initiatives</a> <ul id="initiatives-dropdown" class="f-dropdown dropdown-wrapper dropdown-wrapper__small" data-dropdown-content aria-hidden="true" tabindex="-1"> <li> <div class="row"> <div class="small-12 columns"> <ul> <li> <a href="https://sciforum.net" target="_blank" rel="noopener noreferrer"> Sciforum </a> </li> <li> <a href="https://www.mdpi.com/books" target="_blank" rel="noopener noreferrer"> MDPI Books </a> </li> <li> <a href="https://www.preprints.org" target="_blank" rel="noopener noreferrer"> Preprints.org </a> </li> <li> <a href="https://www.scilit.com" target="_blank" rel="noopener noreferrer"> Scilit </a> </li> <li> <a href="https://sciprofiles.com" target="_blank" rel="noopener noreferrer"> SciProfiles </a> </li> <li> <a href="https://encyclopedia.pub" target="_blank" rel="noopener noreferrer"> Encyclopedia </a> </li> <li> <a href="https://jams.pub" target="_blank" rel="noopener noreferrer"> JAMS </a> </li> <li> <a href="/about/proceedings"> Proceedings Series </a> </li> </ul> </div> </div> </li> </ul> </li> <li class="menu-item"> <a href="/about" data-dropdown="about-dropdown" aria-controls="about-dropdown" aria-expanded="false" data-options="is_hover: true; hover_timeout: 200">About</a> <ul id="about-dropdown" class="f-dropdown dropdown-wrapper dropdown-wrapper__small" data-dropdown-content aria-hidden="true" tabindex="-1"> <li> <div class="row"> <div class="small-12 columns"> <ul> <li> <a href="/about"> Overview </a> </li> <li> <a href="/about/contact"> Contact </a> </li> <li> <a href="https://careers.mdpi.com" target="_blank" rel="noopener noreferrer"> Careers </a> </li> <li> <a href="/about/announcements"> News </a> </li> <li> <a href="/about/press"> Press </a> </li> <li> <a href="http://blog.mdpi.com/" target="_blank" rel="noopener noreferrer"> Blog </a> </li> </ul> </div> </div> </li> </ul> </li> </ul> </div> <div class="large-3 columns text-right full-size-menu__buttons"> <div> <a class="button button--default-inversed UA_SignInUpButton" href="/user/login">Sign In / Sign Up</a> <a class="button button--default js-journal-active-only-link js-journal-active-only-submit-link UC_NavSubmitButton" href=" https://susy.mdpi.com/user/manuscripts/upload?journal=jfb " data-disabledmessage="new submissions are not possible.">Submit</a> </div> </div> </div> </div> <div class="header-divider"> </div> <div class="search-container hide-for-small-down row search-container__homepage-scheme"> <form id="basic_search" style="background-color: inherit !important;" class="large-12 medium-12 columns " action="/search" method="get"> <div class="row search-container__main-elements"> <div class="large-2 medium-2 small-12 columns text-right1 small-only-text-left"> <div class="show-for-medium-up"> <div class="search-input-label"> </div> </div> <span class="search-container__title">Search<span class="hide-for-medium"> for Articles</span><span class="hide-for-small">:</span></span> </div> <div class="custom-accordion-for-small-screen-content"> <div class="large-2 medium-2 small-6 columns "> <div class=""> <div class="search-input-label">Title / Keyword</div> </div> <input type="text" placeholder="Title / Keyword" id="q" tabindex="1" name="q" value="" /> </div> <div class="large-2 medium-2 small-6 columns "> <div class=""> <div class="search-input-label">Author / Affiliation / Email</div> </div> <input type="text" id="authors" placeholder="Author / Affiliation / Email" tabindex="2" name="authors" value="" /> </div> <div class="large-2 medium-2 small-6 columns "> <div class=""> <div class="search-input-label">Journal</div> </div> <select id="journal" tabindex="3" name="journal" class="chosen-select"> <option value="">All Journals</option> <option value="acoustics" > Acoustics </option> <option value="amh" > Acta Microbiologica Hellenica (AMH) </option> <option value="actuators" > Actuators </option> <option value="adhesives" > Adhesives </option> <option value="admsci" > Administrative Sciences </option> <option value="adolescents" > Adolescents </option> <option value="arm" > Advances in Respiratory Medicine (ARM) </option> <option value="aerobiology" > Aerobiology </option> <option value="aerospace" > Aerospace </option> <option value="agriculture" > Agriculture </option> <option value="agriengineering" > AgriEngineering </option> <option value="agrochemicals" > Agrochemicals </option> <option value="agronomy" > Agronomy </option> <option value="ai" > AI </option> <option value="aisens" > AI Sensors </option> <option value="air" > Air </option> <option value="algorithms" > Algorithms </option> <option value="allergies" > Allergies </option> <option value="alloys" > Alloys </option> <option value="analytica" > Analytica </option> <option value="analytics" > Analytics </option> <option value="anatomia" > Anatomia </option> <option value="anesthres" > Anesthesia Research </option> <option value="animals" > Animals </option> <option value="antibiotics" > Antibiotics </option> <option value="antibodies" > Antibodies </option> <option value="antioxidants" > Antioxidants </option> <option value="applbiosci" > Applied Biosciences </option> <option value="applmech" > Applied Mechanics </option> <option value="applmicrobiol" > Applied Microbiology </option> <option value="applnano" > Applied Nano </option> <option value="applsci" > Applied Sciences </option> <option value="asi" > Applied System Innovation (ASI) </option> <option value="appliedchem" > AppliedChem </option> <option value="appliedmath" > AppliedMath </option> <option value="aquacj" > Aquaculture Journal </option> <option value="architecture" > Architecture </option> <option value="arthropoda" > Arthropoda </option> <option value="arts" > Arts </option> <option value="astronomy" > Astronomy </option> <option value="atmosphere" > Atmosphere </option> <option value="atoms" > Atoms </option> <option value="audiolres" > Audiology Research </option> <option value="automation" > Automation </option> <option value="axioms" > Axioms </option> <option value="bacteria" > Bacteria </option> <option value="batteries" > Batteries </option> <option value="behavsci" > Behavioral Sciences </option> <option value="beverages" > Beverages </option> <option value="BDCC" > Big Data and Cognitive Computing (BDCC) </option> <option value="biochem" > BioChem </option> <option value="bioengineering" > Bioengineering </option> <option value="biologics" > Biologics </option> <option value="biology" > Biology </option> <option value="blsf" > Biology and Life Sciences Forum </option> <option value="biomass" > Biomass </option> <option value="biomechanics" > Biomechanics </option> <option value="biomed" > BioMed </option> <option value="biomedicines" > Biomedicines </option> <option value="biomedinformatics" > BioMedInformatics </option> <option value="biomimetics" > Biomimetics </option> <option value="biomolecules" > Biomolecules </option> <option value="biophysica" > Biophysica </option> <option value="biosensors" > Biosensors </option> <option value="biosphere" > Biosphere </option> <option value="biotech" > BioTech </option> <option value="birds" > Birds </option> <option value="blockchains" > Blockchains </option> <option value="brainsci" > Brain Sciences </option> <option value="buildings" > Buildings </option> <option value="businesses" > Businesses </option> <option value="carbon" > C (Journal of Carbon Research) </option> <option value="cancers" > Cancers </option> <option value="cardiogenetics" > Cardiogenetics </option> <option value="catalysts" > Catalysts </option> <option value="cells" > Cells </option> <option value="ceramics" > Ceramics </option> <option value="challenges" > Challenges </option> <option value="ChemEngineering" > ChemEngineering </option> <option value="chemistry" > Chemistry </option> <option value="chemproc" > Chemistry Proceedings </option> <option value="chemosensors" > Chemosensors </option> <option value="children" > Children </option> <option value="chips" > Chips </option> <option value="civileng" > CivilEng </option> <option value="cleantechnol" > Clean Technologies (Clean Technol.) </option> <option value="climate" > Climate </option> <option value="ctn" > Clinical and Translational Neuroscience (CTN) </option> <option value="clinbioenerg" > Clinical Bioenergetics </option> <option value="clinpract" > Clinics and Practice </option> <option value="clockssleep" > Clocks & Sleep </option> <option value="coasts" > Coasts </option> <option value="coatings" > Coatings </option> <option value="colloids" > Colloids and Interfaces </option> <option value="colorants" > Colorants </option> <option value="commodities" > Commodities </option> <option value="complications" > Complications </option> <option value="compounds" > Compounds </option> <option value="computation" > Computation </option> <option value="csmf" > Computer Sciences & Mathematics Forum </option> <option value="computers" > Computers </option> <option value="condensedmatter" > Condensed Matter </option> <option value="conservation" > Conservation </option> <option value="constrmater" > Construction Materials </option> <option value="cmd" > Corrosion and Materials Degradation (CMD) </option> <option value="cosmetics" > Cosmetics </option> <option value="covid" > COVID </option> <option value="cmtr" > Craniomaxillofacial Trauma & Reconstruction (CMTR) </option> <option value="crops" > Crops </option> <option value="cryo" > Cryo </option> <option value="cryptography" > Cryptography </option> <option value="crystals" > Crystals </option> <option value="cimb" > Current Issues in Molecular Biology (CIMB) </option> <option value="curroncol" > Current Oncology </option> <option value="dairy" > Dairy </option> <option value="data" > Data </option> <option value="dentistry" > Dentistry Journal </option> <option value="dermato" > Dermato </option> <option value="dermatopathology" > Dermatopathology </option> <option value="designs" > Designs </option> <option value="diabetology" > Diabetology </option> <option value="diagnostics" > Diagnostics </option> <option value="dietetics" > Dietetics </option> <option value="digital" > Digital </option> <option value="disabilities" > Disabilities </option> <option value="diseases" > Diseases </option> <option value="diversity" > Diversity </option> <option value="dna" > DNA </option> <option value="drones" > Drones </option> <option value="ddc" > Drugs and Drug Candidates (DDC) </option> <option value="dynamics" > Dynamics </option> <option value="earth" > Earth </option> <option value="ecologies" > Ecologies </option> <option value="econometrics" > Econometrics </option> <option value="economies" > Economies </option> <option value="education" > Education Sciences </option> <option value="electricity" > Electricity </option> <option value="electrochem" > Electrochem </option> <option value="electronicmat" > Electronic Materials </option> <option value="electronics" > Electronics </option> <option value="ecm" > Emergency Care and Medicine </option> <option value="encyclopedia" > Encyclopedia </option> <option value="endocrines" > Endocrines </option> <option value="energies" > Energies </option> <option value="esa" > Energy Storage and Applications (ESA) </option> <option value="eng" > Eng </option> <option value="engproc" > Engineering Proceedings </option> <option value="entropy" > Entropy </option> <option value="eesp" > Environmental and Earth Sciences Proceedings </option> <option value="environments" > Environments </option> <option value="epidemiologia" > Epidemiologia </option> <option value="epigenomes" > Epigenomes </option> <option value="ebj" > European Burn Journal (EBJ) </option> <option value="ejihpe" > European Journal of Investigation in Health, Psychology and Education (EJIHPE) </option> <option value="fermentation" > Fermentation </option> <option value="fibers" > Fibers </option> <option value="fintech" > FinTech </option> <option value="fire" > Fire </option> <option value="fishes" > Fishes </option> <option value="fluids" > Fluids </option> <option value="foods" > Foods </option> <option value="forecasting" > Forecasting </option> <option value="forensicsci" > Forensic Sciences </option> <option value="forests" > Forests </option> <option value="fossstud" > Fossil Studies </option> <option value="foundations" > Foundations </option> <option value="fractalfract" > Fractal and Fractional (Fractal Fract) </option> <option value="fuels" > Fuels </option> <option value="future" > Future </option> <option value="futureinternet" > Future Internet </option> <option value="futurepharmacol" > Future Pharmacology </option> <option value="futuretransp" > Future Transportation </option> <option value="galaxies" > Galaxies </option> <option value="games" > Games </option> <option value="gases" > Gases </option> <option value="gastroent" > Gastroenterology Insights </option> <option value="gastrointestdisord" > Gastrointestinal Disorders </option> <option value="gastronomy" > Gastronomy </option> <option value="gels" > Gels </option> <option value="genealogy" > Genealogy </option> <option value="genes" > Genes </option> <option value="geographies" > Geographies </option> <option value="geohazards" > GeoHazards </option> <option value="geomatics" > Geomatics </option> <option value="geometry" > Geometry </option> <option value="geosciences" > Geosciences </option> <option value="geotechnics" > Geotechnics </option> <option value="geriatrics" > Geriatrics </option> <option value="glacies" > Glacies </option> <option value="gucdd" > Gout, Urate, and Crystal Deposition Disease (GUCDD) </option> <option value="grasses" > Grasses </option> <option value="greenhealth" > Green Health </option> <option value="hardware" > Hardware </option> <option value="healthcare" > Healthcare </option> <option value="hearts" > Hearts </option> <option value="hemato" > Hemato </option> <option value="hematolrep" > Hematology Reports </option> <option value="heritage" > Heritage </option> <option value="histories" > Histories </option> <option value="horticulturae" > Horticulturae </option> <option value="hospitals" > Hospitals </option> <option value="humanities" > Humanities </option> <option value="humans" > Humans </option> <option value="hydrobiology" > Hydrobiology </option> <option value="hydrogen" > Hydrogen </option> <option value="hydrology" > Hydrology </option> <option value="hygiene" > Hygiene </option> <option value="immuno" > Immuno </option> <option value="idr" > Infectious Disease Reports </option> <option value="informatics" > Informatics </option> <option value="information" > Information </option> <option value="infrastructures" > Infrastructures </option> <option value="inorganics" > Inorganics </option> <option value="insects" > Insects </option> <option value="instruments" > Instruments </option> <option value="iic" > Intelligent Infrastructure and Construction </option> <option value="ijerph" > International Journal of Environmental Research and Public Health (IJERPH) </option> <option value="ijfs" > International Journal of Financial Studies (IJFS) </option> <option value="ijms" > International Journal of Molecular Sciences (IJMS) </option> <option value="IJNS" > International Journal of Neonatal Screening (IJNS) </option> <option value="ijom" > International Journal of Orofacial Myology and Myofunctional Therapy (IJOM) </option> <option value="ijpb" > International Journal of Plant Biology (IJPB) </option> <option value="ijt" > International Journal of Topology </option> <option value="ijtm" > International Journal of Translational Medicine (IJTM) </option> <option value="ijtpp" > International Journal of Turbomachinery, Propulsion and Power (IJTPP) </option> <option value="ime" > International Medical Education (IME) </option> <option value="inventions" > Inventions </option> <option value="IoT" > IoT </option> <option value="ijgi" > ISPRS International Journal of Geo-Information (IJGI) </option> <option value="J" > J </option> <option value="jal" > Journal of Ageing and Longevity (JAL) </option> <option value="jcdd" > Journal of Cardiovascular Development and Disease (JCDD) </option> <option value="jcto" > Journal of Clinical & Translational Ophthalmology (JCTO) </option> <option value="jcm" > Journal of Clinical Medicine (JCM) </option> <option value="jcs" > Journal of Composites Science (J. Compos. Sci.) </option> <option value="jcp" > Journal of Cybersecurity and Privacy (JCP) </option> <option value="jdad" > Journal of Dementia and Alzheimer's Disease (JDAD) </option> <option value="jdb" > Journal of Developmental Biology (JDB) </option> <option value="jeta" > Journal of Experimental and Theoretical Analyses (JETA) </option> <option value="jemr" > Journal of Eye Movement Research (JEMR) </option> <option value="jfb" selected='selected'> Journal of Functional Biomaterials (JFB) </option> <option value="jfmk" > Journal of Functional Morphology and Kinesiology (JFMK) </option> <option value="jof" > Journal of Fungi (JoF) </option> <option value="jimaging" > Journal of Imaging (J. Imaging) </option> <option value="jintelligence" > Journal of Intelligence (J. Intell.) </option> <option value="jlpea" > Journal of Low Power Electronics and Applications (JLPEA) </option> <option value="jmmp" > Journal of Manufacturing and Materials Processing (JMMP) </option> <option value="jmse" > Journal of Marine Science and Engineering (JMSE) </option> <option value="jmahp" > Journal of Market Access & Health Policy (JMAHP) </option> <option value="jmms" > Journal of Mind and Medical Sciences (JMMS) </option> <option value="jmp" > Journal of Molecular Pathology (JMP) </option> <option value="jnt" > Journal of Nanotheranostics (JNT) </option> <option value="jne" > Journal of Nuclear Engineering (JNE) </option> <option value="ohbm" > Journal of Otorhinolaryngology, Hearing and Balance Medicine (JOHBM) </option> <option value="jop" > Journal of Parks </option> <option value="jpm" > Journal of Personalized Medicine (JPM) </option> <option value="jpbi" > Journal of Pharmaceutical and BioTech Industry (JPBI) </option> <option value="jor" > Journal of Respiration (JoR) </option> <option value="jrfm" > Journal of Risk and Financial Management (JRFM) </option> <option value="jsan" > Journal of Sensor and Actuator Networks (JSAN) </option> <option value="joma" > Journal of the Oman Medical Association (JOMA) </option> <option value="jtaer" > Journal of Theoretical and Applied Electronic Commerce Research (JTAER) </option> <option value="jvd" > Journal of Vascular Diseases (JVD) </option> <option value="jox" > Journal of Xenobiotics (JoX) </option> <option value="jzbg" > Journal of Zoological and Botanical Gardens (JZBG) </option> <option value="journalmedia" > Journalism and Media </option> <option value="kidneydial" > Kidney and Dialysis </option> <option value="kinasesphosphatases" > Kinases and Phosphatases </option> <option value="knowledge" > Knowledge </option> <option value="labmed" > LabMed </option> <option value="laboratories" > Laboratories </option> <option value="land" > Land </option> <option value="languages" > Languages </option> <option value="laws" > Laws </option> <option value="life" > Life </option> <option value="limnolrev" > Limnological Review </option> <option value="lipidology" > Lipidology </option> <option value="liquids" > Liquids </option> <option value="literature" > Literature </option> <option value="livers" > Livers </option> <option value="logics" > Logics </option> <option value="logistics" > Logistics </option> <option value="lubricants" > Lubricants </option> <option value="lymphatics" > Lymphatics </option> <option value="make" > Machine Learning and Knowledge Extraction (MAKE) </option> <option value="machines" > Machines </option> <option value="macromol" > Macromol </option> <option value="magnetism" > Magnetism </option> <option value="magnetochemistry" > Magnetochemistry </option> <option value="marinedrugs" > Marine Drugs </option> <option value="materials" > Materials </option> <option value="materproc" > Materials Proceedings </option> <option value="mca" > Mathematical and Computational Applications (MCA) </option> <option value="mathematics" > Mathematics </option> <option value="medsci" > Medical Sciences </option> <option value="msf" > Medical Sciences Forum </option> <option value="medicina" > Medicina </option> <option value="medicines" > Medicines </option> <option value="membranes" > Membranes </option> <option value="merits" > Merits </option> <option value="metabolites" > Metabolites </option> <option value="metals" > Metals </option> <option value="meteorology" > Meteorology </option> <option value="methane" > Methane </option> <option value="mps" > Methods and Protocols (MPs) </option> <option value="metrics" > Metrics </option> <option value="metrology" > Metrology </option> <option value="micro" > Micro </option> <option value="microbiolres" > Microbiology Research </option> <option value="micromachines" > Micromachines </option> <option value="microorganisms" > Microorganisms </option> <option value="microplastics" > Microplastics </option> <option value="microwave" > Microwave </option> <option value="minerals" > Minerals </option> <option value="mining" > Mining </option> <option value="modelling" > Modelling </option> <option value="mmphys" > Modern Mathematical Physics </option> <option value="molbank" > Molbank </option> <option value="molecules" > Molecules </option> <option value="mti" > Multimodal Technologies and Interaction (MTI) </option> <option value="muscles" > Muscles </option> <option value="nanoenergyadv" > Nanoenergy Advances </option> <option value="nanomanufacturing" > Nanomanufacturing </option> <option value="nanomaterials" > Nanomaterials </option> <option value="ndt" > NDT </option> <option value="network" > Network </option> <option value="neuroglia" > Neuroglia </option> <option value="neurolint" > Neurology International </option> <option value="neurosci" > NeuroSci </option> <option value="nitrogen" > Nitrogen </option> <option value="ncrna" > Non-Coding RNA (ncRNA) </option> <option value="nursrep" > Nursing Reports </option> <option value="nutraceuticals" > Nutraceuticals </option> <option value="nutrients" > Nutrients </option> <option value="obesities" > Obesities </option> <option value="oceans" > Oceans </option> <option value="onco" > Onco </option> <option value="optics" > Optics </option> <option value="oral" > Oral </option> <option value="organics" > Organics </option> <option value="organoids" > Organoids </option> <option value="osteology" > Osteology </option> <option value="oxygen" > Oxygen </option> <option value="parasitologia" > Parasitologia </option> <option value="particles" > Particles </option> <option value="pathogens" > Pathogens </option> <option value="pathophysiology" > Pathophysiology </option> <option value="pediatrrep" > Pediatric Reports </option> <option value="pets" > Pets </option> <option value="pharmaceuticals" > Pharmaceuticals </option> <option value="pharmaceutics" > Pharmaceutics </option> <option value="pharmacoepidemiology" > Pharmacoepidemiology </option> <option value="pharmacy" > Pharmacy </option> <option value="philosophies" > Philosophies </option> <option value="photochem" > Photochem </option> <option value="photonics" > Photonics </option> <option value="phycology" > Phycology </option> <option value="physchem" > Physchem </option> <option value="psf" > Physical Sciences Forum </option> <option value="physics" > Physics </option> <option value="physiologia" > Physiologia </option> <option value="plants" > Plants </option> <option value="plasma" > Plasma </option> <option value="platforms" > Platforms </option> <option value="pollutants" > Pollutants </option> <option value="polymers" > Polymers </option> <option value="polysaccharides" > Polysaccharides </option> <option value="populations" > Populations </option> <option value="poultry" > Poultry </option> <option value="powders" > Powders </option> <option value="proceedings" > Proceedings </option> <option value="processes" > Processes </option> <option value="prosthesis" > Prosthesis </option> <option value="proteomes" > Proteomes </option> <option value="psychiatryint" > Psychiatry International </option> <option value="psychoactives" > Psychoactives </option> <option value="psycholint" > Psychology International </option> <option value="publications" > Publications </option> <option value="qubs" > Quantum Beam Science (QuBS) </option> <option value="quantumrep" > Quantum Reports </option> <option value="quaternary" > Quaternary </option> <option value="radiation" > Radiation </option> <option value="reactions" > Reactions </option> <option value="realestate" > Real Estate </option> <option value="receptors" > Receptors </option> <option value="recycling" > Recycling </option> <option value="rsee" > Regional Science and Environmental Economics (RSEE) </option> <option value="religions" > Religions </option> <option value="remotesensing" > Remote Sensing </option> <option value="reports" > Reports </option> <option value="reprodmed" > Reproductive Medicine (Reprod. Med.) </option> <option value="resources" > Resources </option> <option value="rheumato" > Rheumato </option> <option value="risks" > Risks </option> <option value="robotics" > Robotics </option> <option value="ruminants" > Ruminants </option> <option value="safety" > Safety </option> <option value="sci" > Sci </option> <option value="scipharm" > Scientia Pharmaceutica (Sci. Pharm.) </option> <option value="sclerosis" > Sclerosis </option> <option value="seeds" > Seeds </option> <option value="sensors" > Sensors </option> <option value="separations" > Separations </option> <option value="sexes" > Sexes </option> <option value="signals" > Signals </option> <option value="sinusitis" > Sinusitis </option> <option value="smartcities" > Smart Cities </option> <option value="socsci" > Social Sciences </option> <option value="siuj" > Société Internationale d’Urologie Journal (SIUJ) </option> <option value="societies" > Societies </option> <option value="software" > Software </option> <option value="soilsystems" > Soil Systems </option> <option value="solar" > Solar </option> <option value="solids" > Solids </option> <option value="spectroscj" > Spectroscopy Journal </option> <option value="sports" > Sports </option> <option value="standards" > Standards </option> <option value="stats" > Stats </option> <option value="stresses" > Stresses </option> <option value="surfaces" > Surfaces </option> <option value="surgeries" > Surgeries </option> <option value="std" > Surgical Techniques Development </option> <option value="sustainability" > Sustainability </option> <option value="suschem" > Sustainable Chemistry </option> <option value="symmetry" > Symmetry </option> <option value="synbio" > SynBio </option> <option value="systems" > Systems </option> <option value="targets" > Targets </option> <option value="taxonomy" > Taxonomy </option> <option value="technologies" > Technologies </option> <option value="telecom" > Telecom </option> <option value="textiles" > Textiles </option> <option value="thalassrep" > Thalassemia Reports </option> <option value="therapeutics" > Therapeutics </option> <option value="thermo" > Thermo </option> <option value="timespace" > Time and Space </option> <option value="tomography" > Tomography </option> <option value="tourismhosp" > Tourism and Hospitality </option> <option value="toxics" > Toxics </option> <option value="toxins" > Toxins </option> <option value="transplantology" > Transplantology </option> <option value="traumacare" > Trauma Care </option> <option value="higheredu" > Trends in Higher Education </option> <option value="tropicalmed" > Tropical Medicine and Infectious Disease (TropicalMed) </option> <option value="universe" > Universe </option> <option value="urbansci" > Urban Science </option> <option value="uro" > Uro </option> <option value="vaccines" > Vaccines </option> <option value="vehicles" > Vehicles </option> <option value="venereology" > Venereology </option> <option value="vetsci" > Veterinary Sciences </option> <option value="vibration" > Vibration </option> <option value="virtualworlds" > Virtual Worlds </option> <option value="viruses" > Viruses </option> <option value="vision" > Vision </option> <option value="waste" > Waste </option> <option value="water" > Water </option> <option value="wild" > Wild </option> <option value="wind" > Wind </option> <option value="women" > Women </option> <option value="world" > World </option> <option value="wevj" > World Electric Vehicle Journal (WEVJ) </option> <option value="youth" > Youth </option> <option value="zoonoticdis" > Zoonotic Diseases </option> </select> </div> <div class="large-2 medium-2 small-6 columns "> <div class=""> <div class="search-input-label">Article Type</div> </div> <select id="article_type" tabindex="4" name="article_type" class="chosen-select"> <option value="">All Article Types</option> <option value="research-article">Article</option> <option value="review-article">Review</option> <option value="rapid-communication">Communication</option> <option value="editorial">Editorial</option> <option value="abstract">Abstract</option> <option value="book-review">Book Review</option> <option value="brief-communication">Brief Communication</option> <option value="brief-report">Brief Report</option> <option value="case-report">Case Report</option> <option value="clinicopathological-challenge">Clinicopathological Challenge</option> <option value="article-commentary">Comment</option> <option value="commentary">Commentary</option> <option value="concept-paper">Concept Paper</option> <option value="conference-report">Conference Report</option> <option value="correction">Correction</option> <option value="creative">Creative</option> <option value="data-descriptor">Data Descriptor</option> <option value="discussion">Discussion</option> <option value="Entry">Entry</option> <option value="essay">Essay</option> <option value="expression-of-concern">Expression of Concern</option> <option value="extended-abstract">Extended Abstract</option> <option value="field-guide">Field Guide</option> <option value="giants-in-urology">Giants in Urology</option> <option value="guidelines">Guidelines</option> <option value="hypothesis">Hypothesis</option> <option value="interesting-image">Interesting Images</option> <option value="letter">Letter</option> <option value="books-received">New Book Received</option> <option value="obituary">Obituary</option> <option value="opinion">Opinion</option> <option value="perspective">Perspective</option> <option value="proceedings">Proceeding Paper</option> <option value="project-report">Project Report</option> <option value="protocol">Protocol</option> <option value="registered-report">Registered Report</option> <option value="reply">Reply</option> <option value="retraction">Retraction</option> <option value="note">Short Note</option> <option value="study-protocol">Study Protocol</option> <option value="systematic_review">Systematic Review</option> <option value="technical-note">Technical Note</option> <option value="tutorial">Tutorial</option> <option value="urology-around-the-world">Urology around the World</option> <option value="viewpoint">Viewpoint</option> </select> </div> <div class="large-1 medium-1 small-6 end columns small-push-6 medium-reset-order large-reset-order js-search-collapsed-button-container"> <div class="search-input-label"> </div> <input type="submit" id="search" value="Search" class="button button--dark button--full-width searchButton1 US_SearchButton" tabindex="12"> </div> <div class="large-1 medium-1 small-6 end columns large-text-left small-only-text-center small-pull-6 medium-reset-order large-reset-order js-search-collapsed-link-container"> <div class="search-input-label"> </div> <a class="main-search-clear search-container__link" href="#" onclick="openAdvanced(''); return false;">Advanced<span class="show-for-small-only"> Search</span></a> </div> </div> </div> <div class="search-container__advanced" style="margin-top: 0; padding-top: 0px; background-color: inherit; color: inherit;"> <div class="row"> <div class="large-2 medium-2 columns show-for-medium-up"> </div> <div class="large-2 medium-2 small-6 columns "> <div class=""> <div class="search-input-label">Section</div> </div> <select id="section" tabindex="5" name="section" class="chosen-select"> <option value=""></option> </select> </div> <div class="large-2 medium-2 small-6 columns "> <div class=""> <div class="search-input-label">Special Issue</div> </div> <select id="special_issue" tabindex="6" name="special_issue" class="chosen-select"> <option value=""></option> </select> </div> <div class="large-1 medium-1 small-6 end columns "> <div class="search-input-label">Volume</div> <input type="text" id="volume" tabindex="7" name="volume" placeholder="..." value="15" /> </div> <div class="large-1 medium-1 small-6 end columns "> <div class="search-input-label">Issue</div> <input type="text" id="issue" tabindex="8" name="issue" placeholder="..." value="10" /> </div> <div class="large-1 medium-1 small-6 end columns "> <div class="search-input-label">Number</div> <input type="text" id="number" tabindex="9" name="number" placeholder="..." value="" /> </div> <div class="large-1 medium-1 small-6 end columns "> <div class="search-input-label">Page</div> <input type="text" id="page" tabindex="10" name="page" placeholder="..." value="" /> </div> <div class="large-1 medium-1 small-6 columns small-push-6 medium-reset order large-reset-order medium-reset-order js-search-expanded-button-container"></div> <div class="large-1 medium-1 small-6 columns large-text-left small-only-text-center small-pull-6 medium-reset-order large-reset-order js-search-expanded-link-container"></div> </div> </div> </form> <form id="advanced-search" class="large-12 medium-12 columns"> <div class="search-container__advanced"> <div id="advanced-search-template" class="row advanced-search-row"> <div class="large-2 medium-2 small-12 columns show-for-medium-up"> </div> <div class="large-2 medium-2 small-3 columns connector-div"> <div class="search-input-label"><span class="show-for-medium-up">Logical Operator</span><span class="show-for-small">Operator</span></div> <select class="connector"> <option value="and">AND</option> <option value="or">OR</option> </select> </div> <div class="large-3 medium-3 small-6 columns search-text-div"> <div class="search-input-label">Search Text</div> <input type="text" class="search-text" placeholder="Search text"> </div> <div class="large-2 medium-2 small-6 large-offset-0 medium-offset-0 small-offset-3 columns search-field-div"> <div class="search-input-label">Search Type</div> <select class="search-field"> <option value="all">All fields</option> <option value="title">Title</option> <option value="abstract">Abstract</option> <option value="keywords">Keywords</option> <option value="authors">Authors</option> <option value="affiliations">Affiliations</option> <option value="doi">Doi</option> <option value="full_text">Full Text</option> <option value="references">References</option> </select> </div> <div class="large-1 medium-1 small-3 columns"> <div class="search-input-label"> </div> <div class="search-action-div"> <div class="search-plus"> <i class="material-icons">add_circle_outline</i> </div> </div> <div class="search-action-div"> <div class="search-minus"> <i class="material-icons">remove_circle_outline</i> </div> </div> </div> <div class="large-1 medium-1 small-6 large-offset-0 medium-offset-0 small-offset-3 end columns"> <div class="search-input-label"> </div> <input class="advanced-search-button button button--dark search-submit" type="submit" value="Search"> </div> <div class="large-1 medium-1 small-6 end columns show-for-medium-up"></div> </div> </div> </form> </div> <div class="header-divider"> </div> <div class="breadcrumb row full-row"> <div class="breadcrumb__element"> <a href="/about/journals">Journals</a> </div> <div class="breadcrumb__element"> <a href="/journal/jfb">JFB</a> </div> <div class="breadcrumb__element"> <a href="/2079-4983/15">Volume 15</a> </div> <div class="breadcrumb__element"> <a href="/2079-4983/15/10">Issue 10</a> </div> <div class="breadcrumb__element"> <a href="#">10.3390/jfb15100297</a> </div> </div> </header> <div id="main-content" class=""> <div class="row full-width row-fixed-left-column"> <div id="left-column" class="content__column large-3 medium-3 small-12 columns"> <div class="content__container"> <a href="/journal/jfb"> <img src="https://pub.mdpi-res.com/img/journals/jfb-logo.png?8600e93ff98dbf14" alt="jfb-logo" title="Journal of Functional Biomaterials" style="max-height: 60px; margin: 0 0 0 0;"> </a> <div class="generic-item no-border"> <a class="button button--color button--full-width js-journal-active-only-link js-journal-active-only-submit-link UC_ArticleSubmitButton" href="https://susy.mdpi.com/user/manuscripts/upload?form%5Bjournal_id%5D%3D104" data-disabledmessage="creating new submissions is not possible."> Submit to this Journal </a> <a class="button button--color button--full-width js-journal-active-only-link UC_ArticleReviewButton" href="https://susy.mdpi.com/volunteer/journals/review" data-disabledmessage="volunteering as journal reviewer is not possible."> Review for this Journal </a> <a class="button button--color-inversed button--color-journal button--full-width js-journal-active-only-link UC_ArticleEditIssueButton" href="/journalproposal/sendproposalspecialissue/jfb" data-path="/2079-4983/15/10/297" data-disabledmessage="proposing new special issue is not possible."> Propose a Special Issue </a> </div> <div class="generic-item link-article-menu show-for-small"> <a href="#" class="link-article-menu show-for-small"> <span class="closed">►</span> <span class="open" style="display: none;">▼</span> Article Menu </a> </div> <div class="hide-small-down-initially UI_ArticleMenu"> <div class="generic-item"> <h2>Article Menu</h2> </div> <ul class="accordion accordion__menu" data-accordion data-options="multi_expand:true;toggleable: true"> <li class="accordion-navigation"> <a href="#academic_editors" class="accordion__title">Academic Editor</a> <div id="academic_editors" class="content active"> <div class="academic-editor-container " title="Henry M. Rowan College of Engineering, Department of Chemical Engineering and Biomedical Engineering, Rowan University, Glassboro, NJ, USA"> <div class="sciprofiles-link" style="display: inline-block"> <div class="sciprofiles-link__link"> <img class="sciprofiles-link__image" src="https://pub.mdpi-res.com/bundles/mdpisciprofileslink/img/unknown-user.png?1739771134" style="width: auto; height: 16px; border-radius: 50%;"> <span class="sciprofiles-link__name" style="line-height: 36px;">Andrea Jennifer Vernengo</span> </div> </div> </div> </div> </li> <li class="accordion-direct-link"> <a href="/2079-4983/15/10/297/scifeed_display" data-reveal-id="scifeed-modal" data-reveal-ajax="true">Subscribe SciFeed</a> </li> <li class="accordion-direct-link js-article-similarity-container" style="display: none"> <a href="#" class="js-similarity-related-articles">Recommended Articles</a> </li> <li class="accordion-navigation"> <a href="#related" class="accordion__title">Related Info Links</a> <div id="related" class="content UI_ArticleMenu_RelatedLinks"> <ul> <li class="li-link"> <a href="http://www.ncbi.nlm.nih.gov/sites/entrez/39452595" target="_blank" rel="noopener noreferrer">PubMed/Medline</a> </li> <li class="li-link"> <a href="https://scholar.google.com/scholar?q=3D-Printable%20Gelatin%20Methacrylate-Xanthan%20Gum%20Hydrogel%20Bioink%20Enabling%20Human%20Induced%20Pluripotent%20Stem%20Cell%20Differentiation%20into%20Cardiomyocytes" target="_blank" rel="noopener noreferrer">Google Scholar</a> </li> </ul> </div> </li> <li class="accordion-navigation"> <a href="#authors" class="accordion__title">More by Authors Links</a> <div id="authors" class="content UI_ArticleMenu_AuthorsLinks"> <ul class="side-menu-ul"> <li> <a class="expand" onclick='$(this).closest("li").next("div").toggle(); return false;'>on DOAJ</a> </li> <div id="AuthorDOAJExpand" style="display:none;"> <ul class="submenu"> <li class="li-link"> <a href='http://doaj.org/search/articles?source=%7B%22query%22%3A%7B%22query_string%22%3A%7B%22query%22%3A%22%5C%22Virginia%20Deidda%5C%22%22%2C%22default_operator%22%3A%22AND%22%2C%22default_field%22%3A%22bibjson.author.name%22%7D%7D%7D' target="_blank" rel="noopener noreferrer">Deidda, V.</a> <li> </li> <li class="li-link"> <a href='http://doaj.org/search/articles?source=%7B%22query%22%3A%7B%22query_string%22%3A%7B%22query%22%3A%22%5C%22Isabel%20Ventisette%5C%22%22%2C%22default_operator%22%3A%22AND%22%2C%22default_field%22%3A%22bibjson.author.name%22%7D%7D%7D' target="_blank" rel="noopener noreferrer">Ventisette, I.</a> <li> </li> <li class="li-link"> <a href='http://doaj.org/search/articles?source=%7B%22query%22%3A%7B%22query_string%22%3A%7B%22query%22%3A%22%5C%22Marianna%20Langione%5C%22%22%2C%22default_operator%22%3A%22AND%22%2C%22default_field%22%3A%22bibjson.author.name%22%7D%7D%7D' target="_blank" rel="noopener noreferrer">Langione, M.</a> <li> </li> <li class="li-link"> <a href='http://doaj.org/search/articles?source=%7B%22query%22%3A%7B%22query_string%22%3A%7B%22query%22%3A%22%5C%22Lucrezia%20Giammarino%5C%22%22%2C%22default_operator%22%3A%22AND%22%2C%22default_field%22%3A%22bibjson.author.name%22%7D%7D%7D' target="_blank" rel="noopener noreferrer">Giammarino, L.</a> <li> </li> <li class="li-link"> <a href='http://doaj.org/search/articles?source=%7B%22query%22%3A%7B%22query_string%22%3A%7B%22query%22%3A%22%5C%22Jos%C3%A8%20Manuel%20Pioner%5C%22%22%2C%22default_operator%22%3A%22AND%22%2C%22default_field%22%3A%22bibjson.author.name%22%7D%7D%7D' target="_blank" rel="noopener noreferrer">Pioner, J. Manuel</a> <li> </li> <li class="li-link"> <a href='http://doaj.org/search/articles?source=%7B%22query%22%3A%7B%22query_string%22%3A%7B%22query%22%3A%22%5C%22Caterina%20Credi%5C%22%22%2C%22default_operator%22%3A%22AND%22%2C%22default_field%22%3A%22bibjson.author.name%22%7D%7D%7D' target="_blank" rel="noopener noreferrer">Credi, C.</a> <li> </li> <li class="li-link"> <a href='http://doaj.org/search/articles?source=%7B%22query%22%3A%7B%22query_string%22%3A%7B%22query%22%3A%22%5C%22Federico%20Carpi%5C%22%22%2C%22default_operator%22%3A%22AND%22%2C%22default_field%22%3A%22bibjson.author.name%22%7D%7D%7D' target="_blank" rel="noopener noreferrer">Carpi, F.</a> <li> </li> </ul> </div> <li> <a class="expand" onclick='$(this).closest("li").next("div").toggle(); return false;'>on Google Scholar</a> </li> <div id="AuthorGoogleExpand" style="display:none;"> <ul class="submenu"> <li class="li-link"> <a href="https://scholar.google.com/scholar?q=Virginia%20Deidda" target="_blank" rel="noopener noreferrer">Deidda, V.</a> <li> </li> <li class="li-link"> <a href="https://scholar.google.com/scholar?q=Isabel%20Ventisette" target="_blank" rel="noopener noreferrer">Ventisette, I.</a> <li> </li> <li class="li-link"> <a href="https://scholar.google.com/scholar?q=Marianna%20Langione" target="_blank" rel="noopener noreferrer">Langione, M.</a> <li> </li> <li class="li-link"> <a href="https://scholar.google.com/scholar?q=Lucrezia%20Giammarino" target="_blank" rel="noopener noreferrer">Giammarino, L.</a> <li> </li> <li class="li-link"> <a href="https://scholar.google.com/scholar?q=Jos%C3%A8%20Manuel%20Pioner" target="_blank" rel="noopener noreferrer">Pioner, J. Manuel</a> <li> </li> <li class="li-link"> <a href="https://scholar.google.com/scholar?q=Caterina%20Credi" target="_blank" rel="noopener noreferrer">Credi, C.</a> <li> </li> <li class="li-link"> <a href="https://scholar.google.com/scholar?q=Federico%20Carpi" target="_blank" rel="noopener noreferrer">Carpi, F.</a> <li> </li> </ul> </div> <li> <a class="expand" onclick='$(this).closest("li").next("div").toggle(); return false;'>on PubMed</a> </li> <div id="AuthorPubMedExpand" style="display:none;"> <ul class="submenu"> <li class="li-link"> <a href="http://www.pubmed.gov/?cmd=Search&term=Virginia%20Deidda" target="_blank" rel="noopener noreferrer">Deidda, V.</a> <li> </li> <li class="li-link"> <a href="http://www.pubmed.gov/?cmd=Search&term=Isabel%20Ventisette" target="_blank" rel="noopener noreferrer">Ventisette, I.</a> <li> </li> <li class="li-link"> <a href="http://www.pubmed.gov/?cmd=Search&term=Marianna%20Langione" target="_blank" rel="noopener noreferrer">Langione, M.</a> <li> </li> <li class="li-link"> <a href="http://www.pubmed.gov/?cmd=Search&term=Lucrezia%20Giammarino" target="_blank" rel="noopener noreferrer">Giammarino, L.</a> <li> </li> <li class="li-link"> <a href="http://www.pubmed.gov/?cmd=Search&term=Jos%C3%A8%20Manuel%20Pioner" target="_blank" rel="noopener noreferrer">Pioner, J. Manuel</a> <li> </li> <li class="li-link"> <a href="http://www.pubmed.gov/?cmd=Search&term=Caterina%20Credi" target="_blank" rel="noopener noreferrer">Credi, C.</a> <li> </li> <li class="li-link"> <a href="http://www.pubmed.gov/?cmd=Search&term=Federico%20Carpi" target="_blank" rel="noopener noreferrer">Carpi, F.</a> <li> </li> </ul> </div> </ul> </div> </li> </ul> <span style="display:none" id="scifeed_hidden_flag"></span> <span style="display:none" id="scifeed_subscribe_url">/ajax/scifeed/subscribe</span> </div> </div> <div class="content__container responsive-moving-container large medium active hidden" data-id="article-counters"> <div id="counts-wrapper" class="row generic-item no-border" data-equalizer> <div id="js-counts-wrapper__views" class="small-12 hide columns count-div-container"> <a href="#metrics" > <div class="count-div" data-equalizer-watch> <span class="name">Article Views</span> <span class="count view-number"></span> </div> </a> </div> <div id="js-counts-wrapper__citations" class="small-12 columns hide count-div-container"> <a href="#metrics" > <div class="count-div" data-equalizer-watch> <span class="name">Citations</span> <span class="count citations-number Var_ArticleMaxCitations">-</span> </div> </a> </div> </div> </div> <div class="content__container"> <div class="hide-small-down-initially"> <ul class="accordion accordion__menu" data-accordion data-options="multi_expand:true;toggleable: true"> <li class="accordion-navigation"> <a href="#table_of_contents" class="accordion__title">Table of Contents</a> <div id="table_of_contents" class="content active"> <div class="menu-caption" id="html-quick-links-title"></div> </div> </li> </ul> </div> </div>  <div id="pbgrd-sky"></div> <script src="https://cdn.pbgrd.com/core-mdpi.js"></script> <style>.content__container { min-width: 300px; }</style>  </div> <div id="middle-column" class="content__column large-9 medium-9 small-12 columns end middle-bordered"> <div class="middle-column__help"> <div class="middle-column__help__fixed show-for-medium-up"> <span id="js-altmetrics-donut" href="#" target="_blank" rel="noopener noreferrer" style="display: none;"> <span data-badge-type='donut' class='altmetric-embed' data-doi='10.3390/jfb15100297'></span> <span>Altmetric</span> </span> <a href="#" class="UA_ShareButton" data-reveal-id="main-share-modal" title="Share"> <i class="material-icons">share</i> <span>Share</span> </a> <a href="#" data-reveal-id="main-help-modal" title="Help"> <i class="material-icons">announcement</i> <span>Help</span> </a> <a href="javascript:void(0);" data-reveal-id="cite-modal" data-counterslink = "https://www.mdpi.com/2079-4983/15/10/297/cite" > <i class="material-icons">format_quote</i> <span>Cite</span> </a> <a href="https://sciprofiles.com/discussion-groups/public/10.3390/jfb15100297?utm_source=mpdi.com&utm_medium=publication&utm_campaign=discuss_in_sciprofiles" target="_blank" rel="noopener noreferrer" title="Discuss in Sciprofiles"> <i class="material-icons">question_answer</i> <span>Discuss in SciProfiles</span> </a> </div> <div id="main-help-modal" class="reveal-modal reveal-modal-new" data-reveal aria-labelledby="modalTitle" aria-hidden="true" role="dialog"> <div class="row"> <div class="small-12 columns"> <h2 style="margin: 0;">Need Help?</h2> </div> <div class="small-6 columns"> <h3>Support</h3> <p> Find support for a specific problem in the support section of our website. </p> <a target="_blank" href="/about/contactform" class="button button--color button--full-width"> Get Support </a> </div> <div class="small-6 columns"> <h3>Feedback</h3> <p> Please let us know what you think of our products and services. </p> <a target="_blank" href="/feedback/send" class="button button--color button--full-width"> Give Feedback </a> </div> <div class="small-6 columns end"> <h3>Information</h3> <p> Visit our dedicated information section to learn more about MDPI. </p> <a target="_blank" href="/authors" class="button button--color button--full-width"> Get Information </a> </div> </div> <a class="close-reveal-modal" aria-label="Close"> <i class="material-icons">clear</i> </a> </div> </div> <div class="middle-column__main "> <div class="page-highlight"> <style type="text/css"> img.review-status { width: 30px; } </style> <div id="jmolModal" class="reveal-modal" data-reveal aria-labelledby="Captcha" aria-hidden="true" role="dialog"> <h2>JSmol Viewer</h2> <div class="row"> <div class="small-12 columns text-center"> <iframe style="width: 520px; height: 520px;" frameborder="0" id="jsmol-content"></iframe> <div class="content"></div> </div> </div> <a class="close-reveal-modal" aria-label="Close"> <i class="material-icons">clear</i> </a> </div> <div itemscope itemtype="http://schema.org/ScholarlyArticle" id="abstract" class="abstract_div"> <div class="js-check-update-container"></div> <div class="html-content__container content__container content__container__combined-for-large__first" style="overflow: auto; position: inherit;"> <div class='html-profile-nav'> <div class='top-bar'> <div class='nav-sidebar-btn show-for-large-up' data-status='opened' > <i class='material-icons'>first_page</i> </div> <a id="js-button-download" class="button button--color-inversed" style="display: none;" href="/2079-4983/15/10/297/pdf?version=1728118721" data-name="3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes" data-journal="jfb"> <i class="material-icons custom-download"></i> Download PDF </a> <div class='nav-btn'> <i class='material-icons'>settings</i> </div> <a href="/2079-4983/15/10/297/reprints" id="js-button-reprints" class="button button--color-inversed"> Order Article Reprints </a> </div> <div class='html-article-menu'> <div class='html-first-step row'> <div class='html-font-family large-6 medium-6 small-12 columns'> <div class='row'> <div class='html-font-label large-4 medium-4 small-12 columns'> Font Type: </div> <div class='large-8 medium-8 small-12 columns'> <span class="html-article-menu-option"><i style='font-family:Arial, Arial, Helvetica, sans-serif;' data-fontfamily='Arial, Arial, Helvetica, sans-serif'>Arial</i></span> <span class="html-article-menu-option"><i style='font-family:Georgia1, Georgia, serif;' data-fontfamily='Georgia1, Georgia, serif'>Georgia</i></span> <span class="html-article-menu-option"><i style='font-family:Verdana, Verdana, Geneva, sans-serif;' data-fontfamily='Verdana, Verdana, Geneva, sans-serif' >Verdana</i></span> </div> </div> </div> <div class='html-font-resize large-6 medium-6 small-12 columns'> <div class='row'> <div class='html-font-label large-4 medium-4 small-12 columns'>Font Size:</div> <div class='large-8 medium-8 small-12 columns'> <span class="html-article-menu-option a1" data-percent="100">Aa</span> <span class="html-article-menu-option a2" data-percent="120">Aa</span> <span class="html-article-menu-option a3" data-percent="160">Aa</span> </div> </div> </div> </div> <div class='row'> <div class='html-line-space large-6 medium-6 small-12 columns'> <div class='row'> <div class='html-font-label large-4 medium-4 small-12 columns' >Line Spacing:</div> <div class='large-8 medium-8 small-12 columns'> <span class="html-article-menu-option a1" data-line-height="1.5em"> <i class="fa"></i> </span> <span class="html-article-menu-option a2" data-line-height="1.8em"> <i class="fa"></i> </span> <span class="html-article-menu-option a3" data-line-height="2.1em"> <i class="fa"></i> </span> </div> </div> </div> <div class='html-column-width large-6 medium-6 small-12 columns'> <div class='row'> <div class='html-font-label large-4 medium-4 small-12 columns' >Column Width:</div> <div class='large-8 medium-8 small-12 columns'> <span class="html-article-menu-option a1" data-column-width="20%"> <i class="fa"></i> </span> <span class="html-article-menu-option a2" data-column-width="10%"> <i class="fa"></i> </span> <span class="html-article-menu-option a3" data-column-width="0%"> <i class="fa"></i> </span> </div> </div> </div> </div> <div class='row'> <div class='html-font-bg large-6 medium-6 small-12 columns end'> <div class='row'> <div class='html-font-label large-4 medium-4 small-12 columns'>Background:</div> <div class='large-8 medium-8 small-12 columns'> <div class="html-article-menu-option html-nav-bg html-nav-bright" data-bg="bright"> <i class="fa fa-file-text"></i> </div> <div class="html-article-menu-option html-nav-bg html-nav-dark" data-bg="dark"> <i class="fa fa-file-text-o"></i> </div> <div class="html-article-menu-option html-nav-bg html-nav-creme" data-bg="creme"> <i class="fa fa-file-text"></i> </div> </div> </div> </div> </div> </div> </div> <article ><div class='html-article-content'> <span itemprop="publisher" content="Multidisciplinary Digital Publishing Institute"></span><span itemprop="url" content="https://www.mdpi.com/2079-4983/15/10/297"></span> <div class="article-icons"><span class="label openaccess" data-dropdown="drop-article-label-openaccess" aria-expanded="false">Open Access</span><span class='label choice' data-dropdown='drop-article-label-choice' aria-expanded='false' data-editorschoiceaddition='<a href="/journal/jfb/editors_choice">More Editor’s choice articles in journal <em>Journal of Functional Biomaterials</em>.</a>'>Editor’s Choice</span><span class="label articletype">Article</span></div> <h1 class="title hypothesis_container" itemprop="name"> 3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes </h1> <div class="art-authors hypothesis_container"> by <span class="inlineblock "><div class='profile-card-drop' data-dropdown='profile-card-drop13234954' data-options='is_hover:true, hover_timeout:5000'> Virginia Deidda</div><div id="profile-card-drop13234954" data-dropdown-content class="f-dropdown content profile-card-content" aria-hidden="true" tabindex="-1"><div class="profile-card__title"><div class="sciprofiles-link" style="display: inline-block"><div class="sciprofiles-link__link"><img class="sciprofiles-link__image" src="/bundles/mdpisciprofileslink/img/unknown-user.png" style="width: auto; height: 16px; border-radius: 50%;"><span class="sciprofiles-link__name">Virginia Deidda</span></div></div></div><div class="profile-card__buttons" style="margin-bottom: 10px;"><a href="https://sciprofiles.com/profile/3898407?utm_source=mdpi.com&utm_medium=website&utm_campaign=avatar_name" class="button button--color-inversed" target="_blank"> SciProfiles </a><a href="https://scilit.com/scholars?q=Virginia%20Deidda" class="button button--color-inversed" target="_blank"> Scilit </a><a href="https://www.preprints.org/search?search1=Virginia%20Deidda&field1=authors" class="button button--color-inversed" target="_blank"> Preprints.org </a><a href="https://scholar.google.com/scholar?q=Virginia%20Deidda" class="button button--color-inversed" target="_blank" rels="noopener noreferrer"> Google Scholar </a></div></div><sup> 1</sup><span style="display: inline; margin-left: 5px;"></span><a class="toEncode emailCaptcha visibility-hidden" data-author-id="13234954" href="/cdn-cgi/l/email-protection#406f232e246d2327296f2c6f252d21292c6d30322f34252334292f2e637070712677767074717171267178712671777578717271737126717271727177737670737178712671707126757871267072"><sup><i class="fa fa-envelope-o"></i></sup></a>, </span><span class="inlineblock "><div class='profile-card-drop' data-dropdown='profile-card-drop13234955' data-options='is_hover:true, hover_timeout:5000'> Isabel Ventisette</div><div id="profile-card-drop13234955" data-dropdown-content class="f-dropdown content profile-card-content" aria-hidden="true" tabindex="-1"><div class="profile-card__title"><div class="sciprofiles-link" style="display: inline-block"><div class="sciprofiles-link__link"><img class="sciprofiles-link__image" src="/bundles/mdpisciprofileslink/img/unknown-user.png" style="width: auto; height: 16px; border-radius: 50%;"><span class="sciprofiles-link__name">Isabel Ventisette</span></div></div></div><div class="profile-card__buttons" style="margin-bottom: 10px;"><a href="https://sciprofiles.com/profile/3864330?utm_source=mdpi.com&utm_medium=website&utm_campaign=avatar_name" class="button button--color-inversed" target="_blank"> SciProfiles </a><a href="https://scilit.com/scholars?q=Isabel%20Ventisette" class="button button--color-inversed" target="_blank"> Scilit </a><a href="https://www.preprints.org/search?search1=Isabel%20Ventisette&field1=authors" class="button button--color-inversed" target="_blank"> Preprints.org </a><a href="https://scholar.google.com/scholar?q=Isabel%20Ventisette" class="button button--color-inversed" target="_blank" rels="noopener noreferrer"> Google Scholar </a></div></div><sup> 1</sup><span style="display: inline; margin-left: 5px;"></span><a class="toEncode emailCaptcha visibility-hidden" data-author-id="13234955" href="/cdn-cgi/l/email-protection#28074b464c054b4f410744074d4549414405585a475c4d4b5c4147460b181819491e111810184a184b181d1c1f194e184b181f194c18181949184b194c194c184b1a11194b181f1818184e18181c1f1818194c"><sup><i class="fa fa-envelope-o"></i></sup></a>, </span><span class="inlineblock "><div class='profile-card-drop' data-dropdown='profile-card-drop13234956' data-options='is_hover:true, hover_timeout:5000'> Marianna Langione</div><div id="profile-card-drop13234956" data-dropdown-content class="f-dropdown content profile-card-content" aria-hidden="true" tabindex="-1"><div class="profile-card__title"><div class="sciprofiles-link" style="display: inline-block"><div class="sciprofiles-link__link"><img class="sciprofiles-link__image" src="/bundles/mdpisciprofileslink/img/unknown-user.png" style="width: auto; height: 16px; border-radius: 50%;"><span class="sciprofiles-link__name">Marianna Langione</span></div></div></div><div class="profile-card__buttons" style="margin-bottom: 10px;"><a href="https://sciprofiles.com/profile/3898479?utm_source=mdpi.com&utm_medium=website&utm_campaign=avatar_name" class="button button--color-inversed" target="_blank"> SciProfiles </a><a href="https://scilit.com/scholars?q=Marianna%20Langione" class="button button--color-inversed" target="_blank"> Scilit </a><a href="https://www.preprints.org/search?search1=Marianna%20Langione&field1=authors" class="button button--color-inversed" target="_blank"> Preprints.org </a><a href="https://scholar.google.com/scholar?q=Marianna%20Langione" class="button button--color-inversed" target="_blank" rels="noopener noreferrer"> Google Scholar </a></div></div><sup> 2</sup><span style="display: inline; margin-left: 5px;"></span><a class="toEncode emailCaptcha visibility-hidden" data-author-id="13234956" href="/cdn-cgi/l/email-protection#735c101d175e10141a5c1f5c161e121a1f5e03011c071610071a1c1d5043434310451742154347431043404340431047404342431043404312434743414340434b4117424b434043474311434747404347424a"><sup><i class="fa fa-envelope-o"></i></sup></a><a href="https://orcid.org/0000-0002-7783-2177" target="_blank" rel="noopener noreferrer"><img src="https://pub.mdpi-res.com/img/design/orcid.png?0465bc3812adeb52?1739771134" title="ORCID" style="position: relative; width: 13px; margin-left: 3px; max-width: 13px !important; height: auto; top: -5px;"></a>, </span><span class="inlineblock "><div class='profile-card-drop' data-dropdown='profile-card-drop13234957' data-options='is_hover:true, hover_timeout:5000'> Lucrezia Giammarino</div><div id="profile-card-drop13234957" data-dropdown-content class="f-dropdown content profile-card-content" aria-hidden="true" tabindex="-1"><div class="profile-card__title"><div class="sciprofiles-link" style="display: inline-block"><div class="sciprofiles-link__link"><img class="sciprofiles-link__image" src="/bundles/mdpisciprofileslink/img/unknown-user.png" style="width: auto; height: 16px; border-radius: 50%;"><span class="sciprofiles-link__name">Lucrezia Giammarino</span></div></div></div><div class="profile-card__buttons" style="margin-bottom: 10px;"><a href="https://sciprofiles.com/profile/author/ZVFMZWpub0dKZ1RkUFRUQitlc1Q2ajZDejlTZzFkUkZOWU8zNFp6Z25WST0=?utm_source=mdpi.com&utm_medium=website&utm_campaign=avatar_name" class="button button--color-inversed" target="_blank"> SciProfiles </a><a href="https://scilit.com/scholars?q=Lucrezia%20Giammarino" class="button button--color-inversed" target="_blank"> Scilit </a><a href="https://www.preprints.org/search?search1=Lucrezia%20Giammarino&field1=authors" class="button button--color-inversed" target="_blank"> Preprints.org </a><a href="https://scholar.google.com/scholar?q=Lucrezia%20Giammarino" class="button button--color-inversed" target="_blank" rels="noopener noreferrer"> Google Scholar </a></div></div><sup> 3</sup><span style="display: inline; margin-left: 5px;"></span><a class="toEncode emailCaptcha visibility-hidden" data-author-id="13234957" href="/cdn-cgi/l/email-protection#032c606d672e60646a2c6f2c666e626a6f2e73716c776660776a6c6d203333323a356033653266333a323533363367373133613336336733323332336732663336333133303160323a333133363362333637313336323b"><sup><i class="fa fa-envelope-o"></i></sup></a>, </span><span class="inlineblock "><div class='profile-card-drop' data-dropdown='profile-card-drop13234958' data-options='is_hover:true, hover_timeout:5000'> Josè Manuel Pioner</div><div id="profile-card-drop13234958" data-dropdown-content class="f-dropdown content profile-card-content" aria-hidden="true" tabindex="-1"><div class="profile-card__title"><div class="sciprofiles-link" style="display: inline-block"><div class="sciprofiles-link__link"><img class="sciprofiles-link__image" src="/bundles/mdpisciprofileslink/img/unknown-user.png" style="width: auto; height: 16px; border-radius: 50%;"><span class="sciprofiles-link__name">Josè Manuel Pioner</span></div></div></div><div class="profile-card__buttons" style="margin-bottom: 10px;"><a href="https://sciprofiles.com/profile/771348?utm_source=mdpi.com&utm_medium=website&utm_campaign=avatar_name" class="button button--color-inversed" target="_blank"> SciProfiles </a><a href="https://scilit.com/scholars?q=Jos%C3%A8%20Manuel%20Pioner" class="button button--color-inversed" target="_blank"> Scilit </a><a href="https://www.preprints.org/search?search1=Jos%C3%A8%20Manuel%20Pioner&field1=authors" class="button button--color-inversed" target="_blank"> Preprints.org </a><a href="https://scholar.google.com/scholar?q=Jos%C3%A8%20Manuel%20Pioner" class="button button--color-inversed" target="_blank" rels="noopener noreferrer"> Google Scholar </a></div></div><sup> 4</sup><span style="display: inline; margin-left: 5px;"></span><a class="toEncode emailCaptcha visibility-hidden" data-author-id="13234958" href="/cdn-cgi/l/email-protection#e0cf838e84cd838789cf8ccf858d81898ccd90928f94858394898f8ec3d0d0d0d5d681d1d9d086d0d7d082d0d4d186d086d0d6d4d4d181d0d3d0d5d0d4d086d1d8d281d186d0d4d0d3d083d0d3d4d4d0d3d185"><sup><i class="fa fa-envelope-o"></i></sup></a><a href="https://orcid.org/0000-0003-0179-3033" target="_blank" rel="noopener noreferrer"><img src="https://pub.mdpi-res.com/img/design/orcid.png?0465bc3812adeb52?1739771134" title="ORCID" style="position: relative; width: 13px; margin-left: 3px; max-width: 13px !important; height: auto; top: -5px;"></a>, </span><span class="inlineblock "><div class='profile-card-drop' data-dropdown='profile-card-drop13234959' data-options='is_hover:true, hover_timeout:5000'> Caterina Credi</div><div id="profile-card-drop13234959" data-dropdown-content class="f-dropdown content profile-card-content" aria-hidden="true" tabindex="-1"><div class="profile-card__title"><div class="sciprofiles-link" style="display: inline-block"><div class="sciprofiles-link__link"><img class="sciprofiles-link__image" src="/bundles/mdpisciprofileslink/img/unknown-user.png" style="width: auto; height: 16px; border-radius: 50%;"><span class="sciprofiles-link__name">Caterina Credi</span></div></div></div><div class="profile-card__buttons" style="margin-bottom: 10px;"><a href="https://sciprofiles.com/profile/442523?utm_source=mdpi.com&utm_medium=website&utm_campaign=avatar_name" class="button button--color-inversed" target="_blank"> SciProfiles </a><a href="https://scilit.com/scholars?q=Caterina%20Credi" class="button button--color-inversed" target="_blank"> Scilit </a><a href="https://www.preprints.org/search?search1=Caterina%20Credi&field1=authors" class="button button--color-inversed" target="_blank"> Preprints.org </a><a href="https://scholar.google.com/scholar?q=Caterina%20Credi" class="button button--color-inversed" target="_blank" rels="noopener noreferrer"> Google Scholar </a></div></div><sup> 5,6,*</sup><span style="display: inline; margin-left: 5px;"></span><a class="toEncode emailCaptcha visibility-hidden" data-author-id="13234959" href="/cdn-cgi/l/email-protection#2a0549444e07494d430546054f474b4346075a58455e4f495e434544091a1a1a181c191b1d1a1c1b1b1a4b1a4e1a181e4e1a1a1b1b1a1c1a1d1a4b18191a4b1a4e1a491e4e1a1a1a4e1b1b1e4e1a4b1b1d"><sup><i class="fa fa-envelope-o"></i></sup></a><a href="https://orcid.org/0000-0003-4565-5214" target="_blank" rel="noopener noreferrer"><img src="https://pub.mdpi-res.com/img/design/orcid.png?0465bc3812adeb52?1739771134" title="ORCID" style="position: relative; width: 13px; margin-left: 3px; max-width: 13px !important; height: auto; top: -5px;"></a> and </span><span class="inlineblock "><div class='profile-card-drop' data-dropdown='profile-card-drop13234960' data-options='is_hover:true, hover_timeout:5000'> Federico Carpi</div><div id="profile-card-drop13234960" data-dropdown-content class="f-dropdown content profile-card-content" aria-hidden="true" tabindex="-1"><div class="profile-card__title"><div class="sciprofiles-link" style="display: inline-block"><div class="sciprofiles-link__link"><img class="sciprofiles-link__image" src="/profiles/1503977/thumb/Federico_Carpi.png" style="width: auto; height: 16px; border-radius: 50%;"><span class="sciprofiles-link__name">Federico Carpi</span></div></div></div><div class="profile-card__buttons" style="margin-bottom: 10px;"><a href="https://sciprofiles.com/profile/1503977?utm_source=mdpi.com&utm_medium=website&utm_campaign=avatar_name" class="button button--color-inversed" target="_blank"> SciProfiles </a><a href="https://scilit.com/scholars?q=Federico%20Carpi" class="button button--color-inversed" target="_blank"> Scilit </a><a href="https://www.preprints.org/search?search1=Federico%20Carpi&field1=authors" class="button button--color-inversed" target="_blank"> Preprints.org </a><a href="https://scholar.google.com/scholar?q=Federico%20Carpi" class="button button--color-inversed" target="_blank" rels="noopener noreferrer"> Google Scholar </a></div></div><sup> 1,*</sup><span style="display: inline; margin-left: 5px;"></span><a class="toEncode emailCaptcha visibility-hidden" data-author-id="13234960" href="/cdn-cgi/l/email-protection#1d327e7379307e7a7432713278707c7471306d6f7269787e697472733e2d2d2d2e2b2b2d2f2d2e2c292d7b2d282d2429252d282d2a2c292c2b2d7b2f2b2c2e2d252d7b2d2d2d7b29252d7b2c2f"><sup><i class="fa fa-envelope-o"></i></sup></a><a href="https://orcid.org/0000-0001-8496-5085" target="_blank" rel="noopener noreferrer"><img src="https://pub.mdpi-res.com/img/design/orcid.png?0465bc3812adeb52?1739771134" title="ORCID" style="position: relative; width: 13px; margin-left: 3px; max-width: 13px !important; height: auto; top: -5px;"></a></span> </div> <div class="nrm"></div> <span style="display:block; height:6px;"></span> <div></div> <div style="margin: 5px 0 15px 0;" class="hypothesis_container"> <div class="art-affiliations"> <div class="affiliation "> <div class="affiliation-item"><sup>1</sup></div> <div class="affiliation-name ">Department of Industrial Engineering, University of Florence, 50139 Florence, Italy</div> </div> <div class="affiliation "> <div class="affiliation-item"><sup>2</sup></div> <div class="affiliation-name ">Department of Experimental and Clinical Medicine, University of Florence, 50134 Florence, Italy</div> </div> <div class="affiliation "> <div class="affiliation-item"><sup>3</sup></div> <div class="affiliation-name ">Department of Neurosciences, Psychology, Drug Research and Child Health, University of Florence, 50139 Florence, Italy</div> </div> <div class="affiliation "> <div class="affiliation-item"><sup>4</sup></div> <div class="affiliation-name ">Department of Biology, University of Florence, 50019 Sesto Fiorentino, Italy</div> </div> <div class="affiliation "> <div class="affiliation-item"><sup>5</sup></div> <div class="affiliation-name ">European Laboratory for Non-Linear Spectroscopy, University of Florence, 50019 Sesto Fiorentino, Italy</div> </div> <div class="affiliation "> <div class="affiliation-item"><sup>6</sup></div> <div class="affiliation-name ">National Institute of Optics, National Research Council, 50019 Sesto Fiorentino, Italy</div> </div> <div class="affiliation"> <div class="affiliation-item"><sup>*</sup></div> <div class="affiliation-name ">Authors to whom correspondence should be addressed. </div> </div> </div> </div> <div class="bib-identity" style="margin-bottom: 10px;"> <em>J. Funct. Biomater.</em> <b>2024</b>, <em>15</em>(10), 297; <a href="https://doi.org/10.3390/jfb15100297">https://doi.org/10.3390/jfb15100297</a> </div> <div class="pubhistory" style="font-weight: bold; padding-bottom: 10px;"> <span style="display: inline-block">Submission received: 4 September 2024</span> / <span style="display: inline-block">Revised: 30 September 2024</span> / <span style="display: inline-block">Accepted: 3 October 2024</span> / <span style="display: inline-block">Published: 5 October 2024</span> </div> <div class="belongsTo" style="margin-bottom: 10px;"> (This article belongs to the Special Issue <a href=" /journal/jfb/special_issues/P3CM0961V7 ">State of the Art: Three-Dimensional Printing Materials and Regenerative Medicine</a>)<br/> </div> <div class="highlight-box1"> <div class="download"> <a class="button button--color-inversed button--drop-down" data-dropdown="drop-download-1492689" aria-controls="drop-supplementary-1492689" aria-expanded="false"> Download <i class="material-icons">keyboard_arrow_down</i> </a> <div id="drop-download-1492689" class="f-dropdown label__btn__dropdown label__btn__dropdown--button" data-dropdown-content aria-hidden="true" tabindex="-1"> <a class="UD_ArticlePDF" href="/2079-4983/15/10/297/pdf?version=1728118721" data-name="3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes" data-journal="jfb">Download PDF</a> <br/> <a id="js-pdf-with-cover-access-captcha" href="#" data-target="/2079-4983/15/10/297/pdf-with-cover" class="accessCaptcha">Download PDF with Cover</a> <br/> <a id="js-xml-access-captcha" href="#" data-target="/2079-4983/15/10/297/xml" class="accessCaptcha">Download XML</a> <br/> <a href="/2079-4983/15/10/297/epub" id="epub_link">Download Epub</a> <br/> <a href="javascript:void(0);" data-reveal-id="supplementaryModal">Download Supplementary Material</a> <br/> </div> <div class="js-browse-figures" style="display: inline-block;"> <a href="#" class="button button--color-inversed margin-bottom-10 openpopupgallery UI_BrowseArticleFigures" data-target='article-popup' data-counterslink = "https://www.mdpi.com/2079-4983/15/10/297/browse" >Browse Figures</a> </div> <div id="article-popup" class="popupgallery" style="display: inline; line-height: 200%"> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g001.png?1728118841" title=" <strong>Figure 1</strong><br/> <p>Swelling ratio as a function of time for the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among four samples. A Wilcoxon–Mann–Whitney test indicated a statistically non-significant difference between the GelMA and GelMA-XG series of data (<span class="html-italic">p</span> = 0.2975).</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g002.png?1728118842" title=" <strong>Figure 2</strong><br/> <p>Stress-relative indentation curves of the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among four samples. A Wilcoxon–Mann–Whitney test indicated a statistically significant difference between the GelMA and GelMA-XG series of data (<span class="html-italic">p</span> = 0.0001942).</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g003.png?1728118843" title=" <strong>Figure 3</strong><br/> <p>Degradation ratio as a function of time for the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among two samples. A Wilcoxon–Mann–Whitney test indicated a statistically non-significant difference between the GelMA and GelMA-XG series of data (<span class="html-italic">p</span> = 0.3624).</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g004.png?1728118844" title=" <strong>Figure 4</strong><br/> <p>Example of a structure 3D printed with the GelMA-XG hydrogel.</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g005.png?1728118845" title=" <strong>Figure 5</strong><br/> <p>Assessment of the quality of the extrudable constructs made of the GelMA-XG hydrogel: (<b>A</b>) square frame and example of a 3D-printed version, used to quantify the printing accuracy; (<b>B</b>) grid of square pores and example of a 3D-printed version, used to quantify the printability; zoomed-in views on the right-hand side panel show detailed areas (1, 2, 3) of the printed grid.</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g006.png?1728118849" title=" <strong>Figure 6</strong><br/> <p>Optical microscopy images of hiPSCs within 2D cell cultures on top of layers of the GelMA-XG, GelMA, GelMA-XG-FN and GelMA-FN hydrogels, taken after 4 and 9 days from seeding.</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g007.png?1728118855" title=" <strong>Figure 7</strong><br/> <p>Optical microscopy images of hiPSCs within 3D cell cultures inside hydrogel hemispheres made of GelMA-XG and GelMA-XG-FN. The images were taken after 2 and 7 days from UV cross-linking for 15 s, which occurred above a substrate maintained at a temperature of 25 °C or 15 °C.</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g008.png?1728118858" title=" <strong>Figure 8</strong><br/> <p>Fluorescence microscopy images of the GelMA-XG hydrogel hemispheres containing differentiated hiPSC cardiomyocytes at day 8 of the differentiation process. The differentiation is indicated by the endogenous expression of the mEGFP fluorescent marker. See the videos in the <a href="#app1-jfb-15-00297" class="html-app">Supplementary Materials</a> which show specimens contracting at a frequency of ~0.8 Hz (highest value recorded).</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g009.png?1728118858" title=" <strong>Figure 9</strong><br/> <p>Action potential duration at 90% repolarisation of the differentiated cardiomyocytes inside the GelMA-XG hydrogel hemispheres, on day 17 of the differentiation process, in response to an electrical stimulation at 0.5 Hz or 1 Hz, at 37 °C. The error bars represent the standard deviation among three samples.</p> "> </a> <a href="https://pub.mdpi-res.com/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g010.png?1728118860" title=" <strong>Figure 10</strong><br/> <p>Optical microscopy images of 3D-printed structures made of the hiPSC-laden GelMA-XG hydrogel.</p> "> </a> </div> <a class="button button--color-inversed" href="/2079-4983/15/10/297/notes">Versions Notes</a> </div> </div> <div class="responsive-moving-container small hidden" data-id="article-counters" style="margin-top: 15px;"></div> <div class="html-dynamic"> <section> <div class="art-abstract art-abstract-new in-tab hypothesis_container"> <p> <div><section class="html-abstract" id="html-abstract"> <h2 id="html-abstract-title">Abstract</h2><b>:</b> <div class="html-p">We describe the development of a bioink to bioprint human induced pluripotent stem cells (hiPSCs) for possible cardiac tissue engineering using a gelatin methacrylate (GelMA)-based hydrogel. While previous studies have shown that GelMA at a low concentration (5% <span class="html-italic">w</span>/<span class="html-italic">v</span>) allows for the growth of diverse cells, its 3D printability has been found to be limited by its low viscosity. To overcome that drawback, making the hydrogel both compatible with hiPSCs and 3D-printable, we developed an extrudable GelMA-based bioink by adding xanthan gum (XG). The GelMA-XG composite hydrogel had an elastic modulus (~9 kPa) comparable to that of cardiac tissue, and enabled 3D printing with high values of printing accuracy (83%) and printability (0.98). Tests with hiPSCs showed the hydrogel’s ability to promote their proliferation within both 2D and 3D cell cultures. The tests also showed that hiPSCs inside hemispheres of the hydrogel were able to differentiate into cardiomyocytes, capable of spontaneous contractions (average frequency of ~0.5 Hz and amplitude of ~2%). Furthermore, bioprinting tests proved the possibility of fabricating 3D constructs of the hiPSC-laden hydrogel, with well-defined line widths (~800 μm).</div> </section> <div id="html-keywords"> <div class="html-gwd-group"><div id="html-keywords-title">Keywords: </div><a href="/search?q=3D+bioprinting">3D bioprinting</a>; <a href="/search?q=hydrogel">hydrogel</a>; <a href="/search?q=HiPSCs">HiPSCs</a>; <a href="/search?q=gelatin">gelatin</a>; <a href="/search?q=GelMA">GelMA</a>; <a href="/search?q=xanthan+gum">xanthan gum</a>; <a href="/search?q=cardiac">cardiac</a>; <a href="/search?q=tissue+engineering">tissue engineering</a></div> <div> </div> </div> </div> </p> </div> </section> </div> <div class="hypothesis_container"> <ul class="menu html-nav" data-prev-node="#html-quick-links-title"> </ul> <div class="html-body"> <section id='sec1-jfb-15-00297' type='intro'><h2 data-nested='1'> 1. Introduction</h2><div class='html-p'>Due to the increasing need for organ transplants and the limited number of organ donors, tissue engineering has made progress towards new technologies for tissue development [<a href="#B1-jfb-15-00297" class="html-bibr">1</a>], including cardiac muscle (myocardium) tissue. The myocardium can be subjected to a multitude of insults, such as myocardial infarction, infection, trauma, neoplasms, metabolic disorders and genetic diseases. Under these circumstances, which result in cardiac functional losses, the myocardium presents poor ability to naturally regenerate. One of the most promising regenerative strategies proposed in recent years aims to harness the ability of pluripotent stem cells (PSCs) to differentiate into all tissue types, including cardiac cells; indeed, their use in combination with new biomaterials, capable of emulating the behaviour of the extracellular matrix, represents a new frontier in the realm of cardiac regeneration [<a href="#B2-jfb-15-00297" class="html-bibr">2</a>,<a href="#B3-jfb-15-00297" class="html-bibr">3</a>].</div><div class='html-p'>As for any other tissue, engineering cardiac tissue requires advanced biomanufacturing strategies. At present, the ability of 3D printing to fabricate scaffolds capable of supporting cellular functions is being intensely explored. Conventional strategies typically involve seeding cells onto prefabricated scaffolds, which often results in random distributions of cells, unable to mirror the complex hierarchical organisation of functional tissues. Consequently, 3D printing of cell-laden bioinks, commonly referred to as bioprinting, is being investigated as a possible alternative [<a href="#B4-jfb-15-00297" class="html-bibr">4</a>].</div><div class='html-p'>A variety of bioinks for bioprinting have been developed with the aim of providing embedded cells with a viscoelastic and hydrated microenvironment capable of facilitating nutrient diffusion and extracellular matrix remodelling [<a href="#B5-jfb-15-00297" class="html-bibr">5</a>]. The selection of the bioink material is of paramount importance, as it dictates the physical and chemical properties of the final printed constructs [<a href="#B6-jfb-15-00297" class="html-bibr">6</a>,<a href="#B7-jfb-15-00297" class="html-bibr">7</a>,<a href="#B8-jfb-15-00297" class="html-bibr">8</a>,<a href="#B9-jfb-15-00297" class="html-bibr">9</a>].</div><div class='html-p'>Today, extrusion-based bioprinting is widely used with a diverse range of hydrogels, including natural polymers, such as collagen, gelatin, alginate, fibrin and hyaluronic acid [<a href="#B10-jfb-15-00297" class="html-bibr">10</a>,<a href="#B11-jfb-15-00297" class="html-bibr">11</a>,<a href="#B12-jfb-15-00297" class="html-bibr">12</a>,<a href="#B13-jfb-15-00297" class="html-bibr">13</a>,<a href="#B14-jfb-15-00297" class="html-bibr">14</a>,<a href="#B15-jfb-15-00297" class="html-bibr">15</a>], as well as synthetic polymers, such as poly(ethylene glycol) diacrylates and poloxamers [<a href="#B15-jfb-15-00297" class="html-bibr">15</a>,<a href="#B16-jfb-15-00297" class="html-bibr">16</a>]. Among these, naturally derived hydrogels are especially attractive, because they ensure the highest biocompatibility. In particular, gelatin functionalized with methacrylate groups (GelMA) has been extensively applied in extrudable bioink formulations [<a href="#B17-jfb-15-00297" class="html-bibr">17</a>]. Methacrylate-based modifications of gelatin typically have a dual advantage: they allow for harnessing the unique properties of gelatin, while simultaneously making the material capable of a permanent transition from the liquid to the solid state through chemical reaction of the methacrylate groups [<a href="#B18-jfb-15-00297" class="html-bibr">18</a>]. To this end, the material also requires the addition of a cytocompatible photoinitiator (e.g., Irgacure 2959 or LAP) and the excitation of such with ultra-violet (UV) light, which triggers a radical photopolymerisation reaction [<a href="#B19-jfb-15-00297" class="html-bibr">19</a>]. By varying the GelMA degree of methacrylation and/or the UV power density used for photo-curing, the polymer’s cross-linking density and thus its mechanical and biological properties can be varied [<a href="#B20-jfb-15-00297" class="html-bibr">20</a>]. Accordingly, methacrylated gelatin is widely applied in tissue regeneration [<a href="#B21-jfb-15-00297" class="html-bibr">21</a>].</div><div class='html-p'>To ensure the survival and proliferation of cells, a key role is played by the hydrogel stiffness, which can be adjusted to closely match the native tissue’s stiffness. Studies have reported that cardiac muscle tissue exhibits a stiffness of about 8–12 kPa [<a href="#B22-jfb-15-00297" class="html-bibr">22</a>,<a href="#B23-jfb-15-00297" class="html-bibr">23</a>], and GelMA can show elastic moduli of that order at concentrations between 5% and 10% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> [<a href="#B24-jfb-15-00297" class="html-bibr">24</a>,<a href="#B25-jfb-15-00297" class="html-bibr">25</a>]. Moreover, GelMA has been reported to promote viability of a variety of cell types at concentrations up to ~5% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> [<a href="#B26-jfb-15-00297" class="html-bibr">26</a>,<a href="#B27-jfb-15-00297" class="html-bibr">27</a>,<a href="#B28-jfb-15-00297" class="html-bibr">28</a>].</div><div class='html-p'>However, when GelMA has been used as a bioink at a concentration of 5% for bioprinting, its typically low viscosity has been shown to cause poor retention of shape after extrusion, i.e., poor printability [<a href="#B26-jfb-15-00297" class="html-bibr">26</a>,<a href="#B27-jfb-15-00297" class="html-bibr">27</a>,<a href="#B28-jfb-15-00297" class="html-bibr">28</a>]. Indeed, in general, the printability of a bioink is determined by its viscosity as a trade-off between opposite needs: on one hand, the viscosity should be sufficiently low to ensure ease of extrusion at low pressures, enabling a homogeneous distribution of the cells within the ink and protecting them from excessive shear stresses during the extrusion through sub-millimetric needles; on the other hand, the viscosity should also be sufficiently high to guarantee the preservation of the printed material shape after extrusion during the curing process.</div><div class='html-p'>Nevertheless, when GelMA has been used at concentrations of 10% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> or higher to promote printability, printed structures have been shown to have excessively high stiffness and low porosity, limiting cell viability [<a href="#B27-jfb-15-00297" class="html-bibr">27</a>,<a href="#B28-jfb-15-00297" class="html-bibr">28</a>,<a href="#B29-jfb-15-00297" class="html-bibr">29</a>,<a href="#B30-jfb-15-00297" class="html-bibr">30</a>].</div><div class='html-p'>Therefore, in order to use GelMA hydrogels as bioinks, it is of paramount importance to balance the printability of the material and its biological functionality in terms of cell proliferation and viability. A suitable trade-off between these two requirements remains a challenge in 3D printing of GelMA bioinks [<a href="#B28-jfb-15-00297" class="html-bibr">28</a>].</div><div class='html-p'>To meet this need, it can be useful to combine GelMA with other polymers, such as xanthan gum, alginate or hyaluronic acid [<a href="#B31-jfb-15-00297" class="html-bibr">31</a>,<a href="#B32-jfb-15-00297" class="html-bibr">32</a>]. In particular, xanthan gum (XG) additions have recently been shown to favour increases in the bioink viscosity, ensuring retention of shape after extrusion. For example, Iervolino et al. reported that a bioink based on 7% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> GelMA with the addition of 3% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> XG was printable and able to preserve the shape of printed structures [<a href="#B7-jfb-15-00297" class="html-bibr">7</a>]. The biocompatibility of that formulation was investigated with indirect cytotoxicity tests by exposing L929 cells to a culture medium containing the hydrogel’s degradation products, which were found to be non-cytotoxic [<a href="#B7-jfb-15-00297" class="html-bibr">7</a>]. In the same year, Li et al. developed a novel GelMA/alginate-based composite hydrogel, incorporating polyethylene glycol dimethacrylate and XG to improve printability and control the mechanical properties of the final construct [<a href="#B31-jfb-15-00297" class="html-bibr">31</a>]; bioprinting tests with mesenchymal stem cells demonstrated the ability of the bioink to support cell viability [<a href="#B31-jfb-15-00297" class="html-bibr">31</a>]. While those studies provided preliminary evidence that combining GelMA with XG was able to generate a stable bioink that supported the viability of certain types of cells, the resulting hydrogels exhibited elastic moduli higher than 14 kPa [<a href="#B7-jfb-15-00297" class="html-bibr">7</a>,<a href="#B31-jfb-15-00297" class="html-bibr">31</a>], which are too high for cardiac tissue engineering.</div><div class='html-p'>According to the present state of the art, the aim of this study was to develop a 3D-printable GelMA-based hydrogel bioink satisfying the following two requirements: (i) it should enable the biofabrication of constructs exhibiting an elastic modulus comparable to that of cardiac tissue; (ii) it should preserve the viability and proliferation of human induced pluripotent stem cells (hiPSCs), so as to then promote their differentiation into cardiomyocytes within the hydrogel matrix for cardiac tissue engineering.</div><div class='html-p'>To that end, GelMA was firstly prepared at a concentration of 5% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> and then was combined with XG. The composite bioink was characterised in terms of mechanical properties and 3D printability, as well as proliferation of hiPSCs and their differentiation into cardiac cells.</div></section><section id='sec2-jfb-15-00297' type=''><h2 data-nested='1'> 2. Materials and Methods</h2><section id='sec2dot1-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.1. Hydrogel Preparation</h4><div class='html-p'>The GelMA hydrogel was prepared as follows. Lyophilized GelMA (60% degree of substitution, Sigma Aldrich, St. Louis, MO, USA) was firstly dissolved in either a phosphate-buffered saline solution (PBS 1Χ, pH 7.4, by Gibco, Thermofisher Scientific, Waltham, MA, USA) or a sterile cell culture medium (mTeSR, pH 7.5, by Stem Cell Technologies, Vancouver, Canada) depending on the specific test, as detailed in subsequent sections. The dissolution was performed at a concentration of 5% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> and at a temperature of 40 °C under magnetic stirring until complete dissolution. Then, a photoinitiator (Lithium phenyl-2,4,6-trimethylbenzoylphosphinate—LAP, Sigma Aldrich, St. Louis, MO, USA) was added to the GelMA solution at a concentration of 0.25% <span class='html-italic'>w</span>/<span class='html-italic'>v</span>.</div><div class='html-p'>The GelMA-XG composite hydrogel was prepared by incorporating xanthan gum (Sigma Aldrich, St. Louis, MO, USA) into the GelMA solution at a concentration of 1.25% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> and at a temperature of 40 °C under magnetic stirring. Then, the LAP photoinitiator was added to the GelMA-XG solution at a concentration of 0.25% <span class='html-italic'>w</span>/<span class='html-italic'>v</span>.</div><div class='html-p'>Each type of hydrogel was finally obtained by cross-linking the solution under UV light at a wavelength of 405 nm, generated by the UV LED source of the bioprinter used in this work (Cellink, Goteborg, Sweden—as described in the following). The LED source was used at its maximum intensity (default setting), which was measured (with an optical power meter) and was found to correspond to a power density of 33 mW/cm<sup>2</sup>.</div><div class='html-p'>The duration of cross-linking varied depending on the thickness of the sample to be cured. According to conventional practice and Cellink protocols, we adopted a cross-linking time of approximately 10 s for every 1 mm of specimen thickness.</div></section><section id='sec2dot2-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.2. Bioink Preparation</h4><div class='html-p'>The GelMA-XG solution was also used to prepare a bioink, by mixing it with hiPSCs at varying concentrations, depending on the specific test (as detailed in the subsequent sections). Sterile conditions were ensured by standard procedures (washing with ethanol and UV sterilisation) and a continuous laminar flow.</div><div class='html-p'>The bioink was cross-linked at 405 nm (with an optical power density of 33 mW/cm<sup>2</sup>) for a duration that depended on the sample thickness, as indicated above.</div></section><section id='sec2dot3-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.3. Swelling Test</h4><div class='html-p'>In order to investigate the swelling behaviour, swelling tests were performed on samples of the GelMA and GelMA-XG hydrogels, shaped as 3 mm thick flat specimens, obtained by casting the material into a polydimethylsiloxane (PDMS) mould. All samples were crosslinked at 405 nm (with an optical power density of 33 mW/cm<sup>2</sup>) for 30 s per side.</div><div class='html-p'>The swelling rate of the two hydrogels was studied by incubating the samples at 25 °C in PBS 1Χ and weighing the swollen samples at fixed times, until they reached an equilibrium, i.e., a stabilisation of their weight. In particular, the swelling rate was monitored as the time evolution of the swelling ratio, defined as follows:<div class='html-disp-formula-info' id='FD1-jfb-15-00297'> <div class='f'> <math display='block'><semantics> <mrow> <mi>S</mi> <mi>w</mi> <mi>e</mi> <mi>l</mi> <mi>l</mi> <mi>i</mi> <mi>n</mi> <mi>g</mi> <mo> </mo> <mi>r</mi> <mi>a</mi> <mi>t</mi> <mi>i</mi> <mi>o</mi> <mo>=</mo> <mstyle scriptlevel="0" displaystyle="true"> <mfrac> <mrow> <msub> <mrow> <mi>w</mi> </mrow> <mrow> <mi>s</mi> <mo>,</mo> <mi>t</mi> <mo> </mo> </mrow> </msub> <mo>−</mo> <msub> <mrow> <mi>w</mi> </mrow> <mrow> <mi>d</mi> </mrow> </msub> </mrow> <mrow> <msub> <mrow> <mi>w</mi> </mrow> <mrow> <mi>d</mi> </mrow> </msub> </mrow> </mfrac> </mstyle> <mo> </mo> </mrow> </semantics></math> </div> <div class='l'> <label >(1)</label> </div> </div> where <span class='html-italic'>w<sub>s,t</sub></span> is the weight of the swollen sample at time <span class='html-italic'>t</span> and <span class='html-italic'>w<sub>d</sub></span> is the initial weight of the dried sample.</div></section><section id='sec2dot4-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.4. Quasi-Static Compression Test</h4><div class='html-p'>Indentation tests were performed to characterise the hydrogels’ quasi-static stiffness under compression, which represents a key property for the survival and proliferation of cells within a soft material that mimics the extracellular matrix.</div><div class='html-p'>For each type of hydrogel (GelMA and GelMA-XG), 3 mm thick flat specimens were obtained by mould casting. The samples were cross-linked at 405 nm (with an optical power density of 33 mW/cm<sup>2</sup>) for 30 s per side. Their stiffness was determined in a fully hydrated state. To that end, the samples were firstly immersed in PBS 1Χ at room temperature until they reached swelling equilibrium (i.e., a stabilized weight).</div><div class='html-p'>Then, they were subjected to indentation tests using a custom-built system consisting of a flat cylindrical indenter (diameter of 5 mm) connected to a load cell (HALJIA HX711) mounted on a micrometric three-axial translation stage (product code 7400774616774, Temkin, Waban, MA, USA). Indentation steps equal to 5% of the sample thickness were progressively applied, up to a maximum indentation of 50%. At each step, the force exerted by the specimen in response to the applied indentation was recorded and the related stress was calculated, thereby generating a stress–indentation curve.</div></section><section id='sec2dot5-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.5. Degradation Test</h4><div class='html-p'>In tissue engineering, cell scaffold materials typically need to possess an appropriately tuned degradation rate. In particular, the material should degrade fast enough to leave space for cells to deposit new extracellular matrix; however, the degradation should not be excessively rapid to preserve the mechanical integrity of the printed constructs [<a href="#B7-jfb-15-00297" class="html-bibr">7</a>]. Therefore, a degradation test was performed on the GelMA and GelMA-XG hydrogels as follows.</div><div class='html-p'>For each hydrogel, 3 mm thick specimens were obtained by mould casting, and were cross-linked at 405 nm (with an optical power density of 33 mW/cm<sup>2</sup>) for 30 s per side. The test consisted of maintaining the samples immersed in PBS 1Χ (+0.1% penicillin/streptomycin (P/S)) at 37 °C for 28 days and measuring the progressive reduction in weight over time due to the degradation. The first measurement was taken at 24 h from the beginning of the test in order to ensure that the samples had reached their swelling equilibrium (according to the results of preceding swelling tests, reported in the following). Prior to each measurement, the PBS 1Χ solution was removed, and after the measurement, a new one was added.</div><div class='html-p'>The degradation rate was monitored as the time evolution of the degradation ratio, defined as follows:<div class='html-disp-formula-info' id='FD2-jfb-15-00297'> <div class='f'> <math display='block'><semantics> <mrow> <mi>D</mi> <mi>e</mi> <mi>g</mi> <mi>r</mi> <mi>a</mi> <mi>d</mi> <mi>a</mi> <mi>t</mi> <mi>i</mi> <mi>o</mi> <mi>n</mi> <mo> </mo> <mi>r</mi> <mi>a</mi> <mi>t</mi> <mi>i</mi> <mi>o</mi> <mo>=</mo> <mstyle scriptlevel="0" displaystyle="true"> <mfrac> <mrow> <msub> <mrow> <mi>w</mi> </mrow> <mrow> <mi>s</mi> <mo>,</mo> <mi>e</mi> <mo> </mo> </mrow> </msub> <mo>−</mo> <msub> <mrow> <mi>w</mi> </mrow> <mrow> <mi>d</mi> <mi>e</mi> <mi>g</mi> <mo>,</mo> <mo> </mo> <mi>t</mi> </mrow> </msub> </mrow> <mrow> <msub> <mrow> <mi>w</mi> </mrow> <mrow> <mi>s</mi> <mo>,</mo> <mi>e</mi> </mrow> </msub> </mrow> </mfrac> </mstyle> </mrow> </semantics></math> </div> <div class='l'> <label >(2)</label> </div> </div> where <span class='html-italic'>w<sub>s,e</sub></span> is the initial weight of the swollen hydrogel at equilibrium and <span class='html-italic'>w<sub>deg,t</sub></span> is the weight at time <span class='html-italic'>t</span> of the degraded hydrogel.</div></section><section id='sec2dot6-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.6. Printability Tests</h4><div class='html-p'>Prior to any investigation on the suitability of the GelMA-XG hydrogel as a bioink, its 3D printability was assessed with extrusion tests, aimed at a reaching a trade-off between ability of extrusion through a sub-millimetre needle and shape retention after printing.</div><div class='html-p'>To that end, an extrusion-type bioprinter (BIOX6, Cellink, Goteborg, Sweden) was used to create several horizontal lines by extruding the GelMA-XG hydrogel through a 22G conical needle. A variety of extrusion conditions were experimented with by varying the extrusion temperature at the needle (20 to 26 °C), the extrusion pressure (15 to 25 kPa) and the extrusion speed (5 to 6 mm/s). A suitable trade-off between extrudability and shape retention was empirically achieved with the following printing parameters, identified with trial-and-errors tests: extrusion temperature: 22.5 °C; extrusion pressure: 17 kPa; extrusion speed: 5 mm/s. The samples were cross-linked at 405 nm (with an optical power density of 33 mW/cm<sup>2</sup>) for 15 s on top of a temperature control plate maintained at 15 °C.</div><div class='html-p'>Sterile conditions were ensured by a 5 min UV sterilisation of the printing chamber prior to printing and a continuous laminar flow during printing.</div><div class='html-p'>The quality of the extrudable constructs (determined by the composition of the hydrogel and its printing parameters) was evaluated by quantifying the following two frequently used variables: ‘printing accuracy’ and ‘printability’.</div><div class='html-p'>The printing accuracy was evaluated by comparing the nominal area of a geometric shape to be printed and the actual area of the printed version. According to conventional practice, the employed shape was a square frame. In particular, a 12 × 12 mm square frame with a frame width of 0.41 mm (corresponding to the inner diameter of the extrusion needle) was printed, photographed and analysed (with the ImageJ 1.54i software) to calculate the printed area. The printing accuracy was quantified according to the following formula [<a href="#B33-jfb-15-00297" class="html-bibr">33</a>]:<div class='html-disp-formula-info' id='FD3-jfb-15-00297'> <div class='f'> <math display='block'><semantics> <mrow> <mi>P</mi> <mi>r</mi> <mi>i</mi> <mi>n</mi> <mi>t</mi> <mi>i</mi> <mi>n</mi> <mi>g</mi> <mo> </mo> <mi>a</mi> <mi>c</mi> <mi>c</mi> <mi>u</mi> <mi>r</mi> <mi>a</mi> <mi>c</mi> <mi>y</mi> <mo>=</mo> <mn>1</mn> <mo>−</mo> <mstyle scriptlevel="0" displaystyle="true"> <mfrac> <mrow> <mo> </mo> <mfenced open="|" close="|" separators="|"> <mrow> <msub> <mrow> <mi>A</mi> </mrow> <mrow> <mi>p</mi> <mo> </mo> <mo> </mo> <mo> </mo> </mrow> </msub> <mo>−</mo> <msub> <mrow> <mi>A</mi> </mrow> <mrow> <mi>n</mi> <mo> </mo> <mo> </mo> <mo> </mo> </mrow> </msub> </mrow> </mfenced> </mrow> <mrow> <msub> <mrow> <mi>A</mi> </mrow> <mrow> <mi>n</mi> <mo> </mo> <mo> </mo> <mo> </mo> </mrow> </msub> </mrow> </mfrac> </mstyle> </mrow> </semantics></math> </div> <div class='l'> <label >(3)</label> </div> </div> where <span class='html-italic'>A<sub>n</sub></span> is the nominal area of the frame and <span class='html-italic'>A<sub>p</sub></span> is the area of its printed version. The printing accuracy was averaged among five specimens of the frame.</div><div class='html-p'>The printability was evaluated, according to conventional practice, by printing a 4 × 4 grid of square pores and quantifying for each pore <span class='html-italic'>i</span> the following variable [<a href="#B34-jfb-15-00297" class="html-bibr">34</a>]:<div class='html-disp-formula-info' id='FD4-jfb-15-00297'> <div class='f'> <math display='block'><semantics> <mrow> <mi>P</mi> <mi>r</mi> <mi>i</mi> <mi>n</mi> <mi>t</mi> <mi>a</mi> <mi>b</mi> <mi>i</mi> <mi>l</mi> <mi>i</mi> <mi>t</mi> <mi>y</mi> <mo>=</mo> <mstyle scriptlevel="0" displaystyle="true"> <mfrac> <mrow> <msup> <mrow> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mi>i</mi> <mo> </mo> <mo> </mo> <mo> </mo> </mrow> </msub> </mrow> <mrow> <mn>2</mn> </mrow> </msup> </mrow> <mrow> <mn>16</mn> <mo> </mo> <msub> <mrow> <mi>A</mi> </mrow> <mrow> <mi>i</mi> <mo> </mo> <mo> </mo> <mo> </mo> </mrow> </msub> </mrow> </mfrac> </mstyle> </mrow> </semantics></math> </div> <div class='l'> <label >(4)</label> </div> </div> where <span class='html-italic'>P<sub>i</sub></span> and <span class='html-italic'>A<sub>i</sub></span> are the inner perimeter and inner area, respectively, of the pore. It is worth noting that for a perfect square pore the printability would be 1, while for imperfect printed structures the printability may be higher or lower than 1. In our tests, the grid had a size of 12 × 12 mm with a line width of 0.41 mm (as for the printing accuracy test). The printability was averaged among multiple pores of five specimens of the grid.</div></section><section id='sec2dot7-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.7. HiPSCs Preparation</h4><div class='html-p'>Undifferentiated hiPSCs (cell line AICS-0037 cl.172, Allen Institute for Cell Science, Seattle, WA, USA) were received as a gift (Dr. Albano Meli, CRCN INSERM, Montpellier, France). In the hiPSC clonal line, the gene TNNI1 had endogenously been tagged (by using the CRISPR/Cas9 technology) with the monomeric Enhanced Green Fluorescent Protein (mEGFP), which can be used to track the expression of the slow skeletal Troponin I (ssTnI) sarcomere protein as an indicator of cardiomyocyte differentiation. Indeed, ssTnI is expressed early during any process of cardiac differentiation, including that which leads to hiPSC cardiomyocytes. In particular, as during the early phases of cardiac induction the ssTnI is expressed together with mEGFP, the fluorescence of the latter was used as a marker of successful cardiac differentiation.</div><div class='html-p'>Colonies of the hiPSCs were expanded in mTeSR with +0.1% penicillin/streptomycin (P/S) (Thermo Fisher Scientific, Waltham, MA, USA) on a Matrigel matrix (Corning Incorporated, Corning, NY, USA), at 37 °C and 5% CO<sub>2</sub>. Upon reaching a confluency of 70–80%, the colonies were chemically dissociated by using Tryple 1X (Thermo Fisher Scientific, Waltham, MA, USA) and incubated at 37 °C for approximately 3–5 min. The cell suspension was centrifuged at 200 rpm for 5 min at room temperature and the resulting pellet was resuspended in 1 mL of mTesR (+0.1% P/S) with 5 μM of ROCK inhibitor (Stem Cell Technologies, Vancouver, Canada). The cells were finally used for cell seeding onto hydrogel layers or resuspension into the hydrogel solution, depending on the test to be performed, as described in the following.</div></section><section id='sec2dot8-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.8. HiPSCs Proliferation Test on 2D Cultures</h4><div class='html-p'>The ability of hiPSCs to proliferate within 2D cell cultures on top of layers of the GelMA-XG and GelMA hydrogels was evaluated with preliminary tests. Moreover, to investigate whether the proliferation could be improved with an extracellular matrix protein, the two hydrogel formulations were also supplemented with fibronectin (FN) for comparison according to previous studies [<a href="#B2-jfb-15-00297" class="html-bibr">2</a>].</div><div class='html-p'>For these tests, the GelMA and GelMA-XG hydrogels were prepared according to the procedure described in the previous sections, with the only difference being that the dissolution of GelMA was performed within a culture medium (mTeSR, Stem Cell Technologies, Vancouver, Canada) (+0.1% P/S) instead of PBS 1Χ. To create the new GelMA-XG-FN and GelMA-FN hydrogels, 50 µg/mL of FN (Corning Incorporated, Corning, NY, USA) was added to each formulation.</div><div class='html-p'>Hydrogel layers (1–2 mm thick) were cross-linked at 405 nm (with an optical power density of 33 mW/cm<sup>2</sup>) for 15 s. The layers’ surface was then seeded with hiPSCs (~2 × 10<sup>3</sup> cells/mm<sup>2</sup>) following their chemical dissociation and resuspension within the culture medium (mTeSR, Stem Cell Technologies, Vancouver, Canada) (+0.1% P/S), which was complemented with a ROCK Inhibitor (RI) (Stem Cell Technologies, Vancouver, Canada) at a concentration of 5 μM.</div><div class='html-p'>The specimens were kept in culture at 37 °C and 0.5% CO<sub>2</sub> up to 9 days and were observed with an optical microscope (EVOS FL auto 2, Thermo Fisher Scientific Inc., Waltham, MA, USA).</div></section><section id='sec2dot9-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.9. HiPSCs Proliferation Tests within 3D Cultures</h4><div class='html-p'>To assess the ability of hiPSCs to proliferate within 3D cell cultures inside the GelMA-XG and GelMA-XG-FN hydrogels, the following test was performed.</div><div class='html-p'>The GelMA-XG and GelMA-XG-FN hydrogels were prepared using the same procedure described for the 2D cell cultures tests. HiPSCs were chemically dissociated and resuspended in the mTeSR culture medium (+0.1% P/S), which was complemented with 5 μM RI. The cells were added to the GelMA-XG and GelMA-XG-FN solutions at a concentration of ~2.3 × 10<sup>3</sup> cells/mL.</div><div class='html-p'>Then, small droplets (5–10 μL in volume) of the bioink were pipetted into a multiwell plate and were cross-linked at 405 nm (with an optical power density of 33 mW/cm<sup>2</sup>) for 15 s. Moreover, to investigate the effect of the temperature of the substrate above which the hydrogels where cross-liked, the cross-linking was performed on top of a temperature control plate, which was used to apply different temperatures to different samples: 25 °C or 15 °C. This was aimed at assessing the role that the temperature of the printing bed would have during a 3D printing and curing process. Therefore, the temperature control plate adopted for this test coincided with the heated print bed of the bioprinter.</div><div class='html-p'>Subsequently, the so-created cell-laden hydrogel hemispheres were cultured in the mTeSR culture medium (+0.1% P/S) with the addition of RI at a concentration of 5 μM at 37 °C and 5% CO<sub>2</sub> for 7 days. Optical microscope images (Olympus CKX53, Evident Corporation, Tokyo, Japan) were acquired at regular intervals.</div></section><section id='sec2dot10-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.10. HiPSCs Cardiac Differentiation Tests within 3D Cultures</h4><div class='html-p'>On day 7 of culturing of the cell-laden GelMA-XG hydrogel hemispheres, the cell differentiation process was initiated using the PSC Cardiomyocyte Differentiation Kit (Thermo Fisher Scientific Inc., Waltham, MA, USA). In particular, the process started by adding the differentiation medium A of the kit. This corresponded with day 0 of the differentiation protocol. After two days, medium A was replaced with the differentiation medium B, which was subsequently replaced, after two days, with the maintenance medium C. Then, the maintenance medium C was changed every two days. From day 12 of cellular maturation, the samples were maintained in the RPMI/B27 medium (Thermo Fisher Scientific Inc., Waltham, MA, USA) (+0.1% P/S).</div><div class='html-p'>Subsequently, images were acquired using a fluorescence microscope (EVOS FL auto 2, Thermo Fisher Scientific Inc., Waltham, MA, USA). This allowed for the visualisation of the fluorescence emission by the mEGFP-labelled slow skeletal Troponin I, which was expressed only by the cells that had been differentiated into cardiomyocytes.</div><div class='html-p'>Additionally, confocal microscopy tests were performed to analyse the action potentials generated by the matured cardiomyocytes. The samples were stained with 1 μL/mL of an electrically sensitive fluorescent dye (Di-8-ANEPPS, Thermo Fisher, Waltham, MA, USA), which was used as an optical probe of the cell membrane potential. The dye was added to the Tyrode experimental solution (5 mM HEPES, 10 mM Glucose, 140 mM NaC1, 5.4 mM KCI, 1.2 mM MgCl<sub>2</sub>, mM 1.8 CaCl<sub>2</sub>, pH = 7.3) inside an experimental chamber. The chamber was equipped with platinum electrodes used to deliver controlled electrical stimulation. The latter consisted of repeated voltage pulse trains (90 V pulse amplitude, for an electrode separation of 1 cm) generated by an external stimulator (DigiTimer, Welwyn Garden City, UK). Each train consisted of a ~50 ms sequence of pulses, each having a duration (pulse width) of 0.08 ms. The pulse trains were repeated at a frequency of either 0.5 or 1 Hz for the sake of comparison.</div><div class='html-p'>During the recordings, the samples were continuously perfused with Tyrode solution heated to 37 °C. A blue LED light (467 nm) was used for fluorescence studies to excite the dye in the samples. The emitted fluorescence was collected by a camera (Photometrics Prime sCOS Teledyne, Tucson, AZ, USA) and processed through a dual-wavelength bandpass filter cube (IDEX, Semrock, West Henrietta, NY, USA). The filter allowed for collecting orange radiation (631 nm) corresponding to the emission of the dye. The fluorescence images were analysed using a proprietary software (MetaMorph, Molecular Devices, San Jose, CA, USA). Data related to various regions of interest were acquired from each sample.</div></section><section id='sec2dot11-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.11. HiPSCs Bioprinting Test</h4><div class='html-p'>In order to perform preliminary bioprinting tests, the GelMA-XG hydrogel was prepared using the same procedure described for the 2D and 3D cell cultures tests. HiPSCs were chemically dissociated and resuspended in the mTeSR culture medium (+0.1% P/S), which was complemented with 5 μM RI. To create the bioink, the cells were added to the GelMA-XG solution, at a concentration of ~1.3 × 10<sup>3</sup> cells/mL. Once the bioink was balanced at 37 °C, it was transferred to the print cartridge, which was then mounted on the bioprinter (BIOX6, Cellink, Goteborg, Sweden).</div><div class='html-p'>Test lines were 3D printed with the bioink and cross-linked at 405 nm (with an optical power density of 33 mW/cm<sup>2</sup>) for 15 s.</div></section><section id='sec2dot12-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 2.12. Statistical Analysis</h4><div class='html-p'>Quantitative results were expressed as mean values ± standard deviation. In consideration of the small number of samples available for each type of measurement, it was not possible to verify the data distribution’s normality. Therefore, non-parametric statistical analyses were performed, using the Wilcoxon–Mann–Whitney test. The test was implemented within the software R (R Core Team, Vienna, Austria), using the function ‘wilcox.test()’. Differences were considered statistically significant for <span class='html-italic'>p</span> < 0.05.</div></section></section><section id='sec3-jfb-15-00297' type='results'><h2 data-nested='1'> 3. Results and Discussion</h2><section id='sec3dot1-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 3.1. Hydrogel Swelling</h4><div class='html-p'><a href="#jfb-15-00297-f001" class="html-fig">Figure 1</a> presents the swelling dynamics of the GelMA and GelMA-XG hydrogels. The swelling ratio increased over time until equilibrium, which was reached after about 5 h.</div><div class='html-p'>These swelling tests indicated that the hydrogel’s ability to absorb water was not significantly affected by the presence of XG. Indeed, while the swelling ratio at equilibrium appeared slightly higher for GelMA (<a href="#jfb-15-00297-f001" class="html-fig">Figure 1</a>), no statistically significant difference was obtained relative to GelMa-XG (<span class='html-italic'>p</span> > 0.05). This likely occurred because of two concomitant antagonist effects induced by the addition of XG: on one hand, it created an interpenetrating polymer network, which tended to increase the material’s density and stiffness, as also confirmed by the results of the indentation tests (presented below); however, on the other hand, it also decreased the cross-link density (because of a reduction in the density of methacrylate groups), thereby facilitating the GelMA swelling.</div></section><section id='sec3dot2-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 3.2. Hydrogel Stiffness</h4><div class='html-p'>The characterisation of the quasi-static stiffness of the GelMA and GelMA-XG hydrogels under compression is presented in <a href="#jfb-15-00297-f002" class="html-fig">Figure 2</a>, which plots the compressive stress as a function of the relative indentation (defined as the ratio between the absolute value of the reduction in thickness of the sample and its thickness at rest).</div><div class='html-p'>The compressive elastic modulus of each hydrogel was estimated as the initial slope of a second-order fitting curve for the data. The GelMA hydrogel exhibited an elastic modulus of ~4 kPa, which was consistent with findings reported in the literature [<a href="#B35-jfb-15-00297" class="html-bibr">35</a>].</div><div class='html-p'>However, the addition of XG led to an increase in stiffness, resulting in a compressive elastic modulus of ~9 kPa. This value was comparable with those reported for the cardiac muscle tissue (8–12 kPa) [<a href="#B22-jfb-15-00297" class="html-bibr">22</a>,<a href="#B23-jfb-15-00297" class="html-bibr">23</a>]. This indicates that the GelMA-XG hydrogel can adequately match the mechanical properties of the biological tissue of interest.</div></section><section id='sec3dot3-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 3.3. Hydrogel Degradation</h4><div class='html-p'>The degradation ratio of the GelMA and GelMA-XG hydrogels as a function of time is shown in <a href="#jfb-15-00297-f003" class="html-fig">Figure 3</a>.</div><div class='html-p'>As compared to the GelMA hydrogel, the GelMA-XG composite did not exhibit statistically significant differences in terms of degradation. Indeed, while the degradation ratio appeared as slightly higher for GelMA (<a href="#jfb-15-00297-f003" class="html-fig">Figure 3</a>), no statistically significant difference was obtained relative to GelMA-XG (<span class='html-italic'>p</span> > 0.05). Such an outcome was consistent with the results of the swelling test (<a href="#jfb-15-00297-f001" class="html-fig">Figure 1</a>).</div></section><section id='sec3dot4-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 3.4. Hydrogel Printability</h4><div class='html-p'>As a qualitative example of the printability of the GelMA-XG hydrogel, <a href="#jfb-15-00297-f004" class="html-fig">Figure 4</a> presents a 3D-printed structure.</div><div class='html-p'>As an assessment of the quality of the extrudable constructs, <a href="#jfb-15-00297-f005" class="html-fig">Figure 5</a> presents the geometric shapes that were 3D printed with the GelMA-XG hydrogel to quantify the ‘printing accuracy’ and ‘printability’.</div><div class='html-p'>In particular, <a href="#jfb-15-00297-f005" class="html-fig">Figure 5</a>A shows an example of a 3D-printed square, which was used to measure the printing accuracy. By taking measurements from five specimens, the average printing accuracy was 83% (with an error of ±9%). This outcome, which was consistent with findings from other studies on 3D printing of gelatin-based bioinks [<a href="#B33-jfb-15-00297" class="html-bibr">33</a>,<a href="#B36-jfb-15-00297" class="html-bibr">36</a>], indicates that the combined hydrogel and printing process enabled the fabrication of structures with rather good accuracy, due to an ability to retain shape after extrusion.</div><div class='html-p'><a href="#jfb-15-00297-f005" class="html-fig">Figure 5</a>B presents an example of a 3D-printed grid used to measure the printability. By taking measurements from five specimens, the average printability was 0.98 (with an error of ±0.02). This number was not only included within the range of values (from 0.9 to 1.1) that are typically regarded as indicative of good printing properties [<a href="#B34-jfb-15-00297" class="html-bibr">34</a>], but also very close to the ideal case (printability = 1). This demonstrates the high printability of the GelMA-XG hydrogel.</div><div class='html-p'>For the sake of comparisons, it is worth noting that the achieved printability was higher than the values (from 0.89 to 0.91) previously reported for GelMA at a concentration of 10% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> [<a href="#B4-jfb-15-00297" class="html-bibr">4</a>]. Therefore, this shows that the creation of a composite between GelMA at a concentration of 5% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> and XG was more effective, in terms of printability, than simply increasing the GelMA concentration to 10% <span class='html-italic'>w</span>/<span class='html-italic'>v</span> (without any addition of XG).</div></section><section id='sec3dot5-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 3.5. HiPSCs Proliferation on 2D Cultures</h4><div class='html-p'>The results of a preliminary test of hiPSC proliferation on the GelMA-XG, GelMA, GelMA-XG-FN and GelMA-FN hydrogels are presented in <a href="#jfb-15-00297-f006" class="html-fig">Figure 6</a>.</div><div class='html-p'>From day 4 to day 9, the number and size of cell colonies increased for all materials, indicating that all of them enabled the proliferation of the cells.</div><div class='html-p'>The addition of fibronectin to the formulations was not found to lead to evident significant differences in terms of cell proliferation, as shown by the images in <a href="#jfb-15-00297-f006" class="html-fig">Figure 6</a>.</div></section><section id='sec3dot6-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 3.6. HiPSC Proliferation within 3D Cultures</h4><div class='html-p'>The hiPSC proliferation within 3D cell cultures inside the GelMA-XG and GelMA-XG-FN hydrogel hemispheres is presented in <a href="#jfb-15-00297-f007" class="html-fig">Figure 7</a>.</div><div class='html-p'>The images show that both hydrogels facilitated the cellular proliferation. As for the 2D cell culture tests, even in these tests the addition of fibronectin was not found to cause evident differences in terms of cellular proliferation.</div><div class='html-p'><a href="#jfb-15-00297-f007" class="html-fig">Figure 7</a> also presents the effect of a variation of the temperature of the substrate above which the hydrogels were cross-linked (by UV irradiation). This provides preliminary information, which might be useful to plan future bioprinting strategies. Indeed, they might take advantage of cooling the 3D printing bed to reduce the viscosity of the extruded material and facilitate the retention of shape during cross-linking. The results in <a href="#jfb-15-00297-f007" class="html-fig">Figure 7</a> show that cooling the substrate down to 15 °C did not apparently limit the ability of the cells to proliferate. Nevertheless, such preliminary evidence provides initial indications that necessarily cannot be taken as conclusive, as they should be confirmed with future systematic studies.</div></section><section id='sec3dot7-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 3.7. HiPSC Cardiac Differentiation within 3D Cultures</h4><div class='html-p'>Eight days after the initiation of the differentiation process within the cell-laden GelMA-XG and GelMA-XG-FN hydrogel hemispheres, the cells exhibited significant spontaneous contraction, which revealed their differentiation into cardiomyocytes. Videos showing contractions of the differentiated cells are available in the <a href="#app1-jfb-15-00297" class="html-app">Supplementary Materials</a>.</div><div class='html-p'>The differentiation was also evidenced by the fluorescence caused by the expression of the mEGFP-labelled slow skeletal Troponin I in the cell sarcomeres, as shown in <a href="#jfb-15-00297-f008" class="html-fig">Figure 8</a>. The fluorescence was used a reliable indicator, as hiPSC cardiomyocytes are well known to express, early after cardiac differentiation, that type of Troponin [<a href="#B37-jfb-15-00297" class="html-bibr">37</a>], which is therefore widely used as a cardiac maturation marker of hiPSC cardiomyocytes.</div><div class='html-p'>The frequency and amplitude of contraction were measured by processing the videos (with the software ImageJ). On day 8 from the beginning of the differentiation process, different specimens of the GelMA-XG and GelMA-XG-FN hydrogel hemispheres were found to exhibit an average contraction frequency of 0.5 Hz (±0.2 Hz standard deviation) and 0.3 Hz (±0.1 Hz standard deviation), respectively, while their average contraction amplitude was 2.0% (±1.5% standard deviation) and 1.1% (±1.4% standard deviation), respectively. Such values of frequency and amplitude were consistent with those of immature cardiomyocytes [<a href="#B38-jfb-15-00297" class="html-bibr">38</a>]. This was likely due to the structural/functional immaturity of the cardiomyocytes (on day 8 from the beginning of the differentiation), as well as the fact that the recordings took place at room temperature (~23 °C).</div><div class='html-p'>The differentiated cardiomyocytes were also subjected to a fluorescence-based optical analysis of action potentials induced by electrical stimulation (as detailed in the Materials and Methods section). In particular, the analysis was used to determine the action potential duration at 90% repolarisation (APD90%), the values of which are presented in <a href="#jfb-15-00297-f009" class="html-fig">Figure 9</a>.</div><div class='html-p'>The average values (230 and 268 ms) were consistent with those reported in the literature for single hiPSC cardiomyocytes [<a href="#B39-jfb-15-00297" class="html-bibr">39</a>,<a href="#B40-jfb-15-00297" class="html-bibr">40</a>], although they were lower than typical values (~350 ms) of mature cardiomyocytes [<a href="#B41-jfb-15-00297" class="html-bibr">41</a>]. These results indicated that the electro-physiological phenotype of the differentiated cardiomyocytes was distinct from that of adult cardiomyocytes, due to different expressions of ionic channels, owing to the cardiomyocytes’ immaturity [<a href="#B42-jfb-15-00297" class="html-bibr">42</a>,<a href="#B43-jfb-15-00297" class="html-bibr">43</a>].</div></section><section id='sec3dot8-jfb-15-00297' type=''><h4 class='html-italic' data-nested='2'> 3.8. HiPSCs Bioprinting</h4><div class='html-p'>The results of a preliminary test of bioprinting of the hiPSC-laden GelMA-XG bioink are presented in <a href="#jfb-15-00297-f010" class="html-fig">Figure 10</a>.</div><div class='html-p'>The 3D-printed structures showed a high retention of shape, with well-defined edges and a line width of ~800 μm.</div><div class='html-p'>However, the structures were found to display a low cell density, as visible in the images; this might straightforwardly be addressed in the future by increasing the cell concentration in the bioink above the value used in these preliminary tests (~1.3 × 10<sup>3</sup> cells/mL).</div></section></section><section id='sec4-jfb-15-00297' type='conclusions'><h2 data-nested='1'> 4. Conclusions and Future Developments</h2><div class='html-p'>We described the development of a bioink formulation for bioprinting of human induced pluripotent stem cells using a GelMA-based hydrogel.</div><div class='html-p'>Although previous studies had shown that GelMA at a low concentration (5% <span class='html-italic'>w</span>/<span class='html-italic'>v</span>) allowed the growth of a diversity of cells, GelMA was also known to limit the 3D printability of structures, owing to a poor retention of shape after extrusion caused by a low viscosity. To solve that problem, ensuring both a good printability of the bioink and high proliferations of stem cells, in this work a 3D-printable GelMA-based bioink was developed with the addition of XG.</div><div class='html-p'>The GelMA-XG hydrogel was shown to have a compressive elastic modulus (~9 kPa) comparable to that of cardiac tissue, as well as enable 3D printing, being characterised by high values of printing accuracy (83%) and printability (0.98).</div><div class='html-p'>Tests with human induced pluripotent stem cells showed the hydrogel’s ability to promote their proliferation within both 2D and 3D cell cultures. The tests also showed that stem cells inside hemispheres of the hydrogel were able to differentiate into colonies of cardiomyocytes, which displayed spontaneous contractile activity (average contraction frequency of ~0.5 Hz and amplitude of ~2%).</div><div class='html-p'>Preliminary bioprinting tests demonstrated the possibility of extruding the cell-laden hydrogel, producing structures with well-defined line widths (~800 μm).</div><div class='html-p'>Future studies might extend this preliminary work by performing more systematic investigations. In particular, the number of samples to be tested for each type of characterisation should be increased to enable meaningful statistical analyses. Furthermore, the tests might be complemented with additional ones, such as the measurement of the materials’ rheological and morphological properties. Nevertheless, the most important goal should be assessing how 3D structures that will be printed using the new bioink will behave in terms of stem cell viability, proliferation and differentiation.</div></section> </div> <div class="html-back"> <section><section id='app1-jfb-15-00297' type=''><h2 data-nested='1'> Supplementary Materials</h2><div class='html-p'>The following supporting information can be downloaded at: <a href='https://www.mdpi.com/article/10.3390/jfb15100297/s1' target='_blank' rel="noopener noreferrer">https://www.mdpi.com/article/10.3390/jfb15100297/s1</a>: Video S1, Fluorescence microscopy of the spontaneous contraction of differentiated hiPSC-cardiomyocytes inside GelMA-XG hydrogel hemispheres; Video S2, Optical microscopy of the spontaneous contraction of differentiated hiPSC-cardiomyocytes inside GelMA-XG hydrogel hemispheres.</div></section></section><section class='html-notes'><h2 >Author Contributions</h2><div class='html-p'>Conceptualisation, J.M.P., C.C. and F.C.; methodology for hydrogel formulation, V.D., I.V. and C.C.; methodology for cell culture and cardiomyocyte experiments, M.L., L.G. and J.M.P.; formal analysis, V.D., I.V., M.L., J.M.P., C.C. and F.C.; resources, J.M.P., C.C. and F.C.; data curation, V.D., I.V. and M.L.; writing—original draft preparation, V.D. and I.V.; writing—review and editing, V.D., I.V., J.M.P., C.C. and F.C.; supervision, J.M.P., C.C. and F.C.; funding, J.M.P., C.C. and F.C. All authors have read and agreed to the published version of the manuscript.</div></section><section class='html-notes'><h2>Funding</h2><div class='html-p'>This research was funded by the Italian Ministry of University and Research (PNRR project “AGE-IT—Ageing well in an ageing society” (F.C.), PNRR project “Integrated infrastructure initiative in photonic and quantum sciencesI-PHOQS” (C.C.) and PRIN2022 project 20223L2C9N “The Role of Cardiac Extracellular matrix—Cell interaction in the onset of dystrophic cardiomyopathies (MALADAPT)” (J.M.P.)), the Italian Ministry of Health (project GR-2021-12375403 “Precision medicine in dystrophin cardiomyopathies—characterization of induced pluripotent stem cells (iPSC) derived from Duchenne patients with advanced heart failure using artificial intelligence to differentiate disease pathways and identify predictors for treatment response” (J.M.P.)) and by Fondazione Cassa di Risparmio di Firenze, Italy (project “Lab Didattici Ingegneria Biomedica” (F.C.)).</div></section><section class='html-notes'><h2 >Institutional Review Board Statement</h2><div class='html-p'>Not applicable.</div></section><section class='html-notes'><h2 >Informed Consent Statement</h2><div class='html-p'>Not applicable.</div></section><section class='html-notes'><h2 >Data Availability Statement</h2><div class='html-p'>The data that support the findings of this study are available from the corresponding author upon reasonable request.</div></section><section class='html-notes'><h2 >Conflicts of Interest</h2><div class='html-p'>The authors declare no conflicts of interest.</div></section><section id='html-references_list'><h2>References</h2><ol class='html-xx'><li id='B1-jfb-15-00297' class='html-x' data-content='1.'>Zorlutuna, P.; Annabi, N.; Camci-Unal, G.; Nikkhah, M.; Cha, J.M.; Nichol, J.W.; Manbachi, A.; Bae, H.; Chen, S.; Khademhosseini, A. Microfabricated biomaterials for engineering 3D tissues. <span class='html-italic'>Adv. Mater.</span> <b>2012</b>, <span class='html-italic'>24</span>, 1782–1804. [<a href="https://scholar.google.com/scholar_lookup?title=Microfabricated+biomaterials+for+engineering+3D+tissues&author=Zorlutuna,+P.&author=Annabi,+N.&author=Camci-Unal,+G.&author=Nikkhah,+M.&author=Cha,+J.M.&author=Nichol,+J.W.&author=Manbachi,+A.&author=Bae,+H.&author=Chen,+S.&author=Khademhosseini,+A.&publication_year=2012&journal=Adv.+Mater.&volume=24&pages=1782%E2%80%931804&doi=10.1002/adma.201104631&pmid=22410857" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1002/adma.201104631" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/22410857" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B2-jfb-15-00297' class='html-x' data-content='2.'>Kupfer, M.E.; Lin, W.H.; Ravikumar, V.; Qiu, K.; Wang, L.; Gao, L.; Bhuiyan, D.B.; Lenz, M.; Ai, J.; Mahutga, R.R.; et al. In situ expansion, differentiation, and electromechanical coupling of human cardiac muscle in a 3D bioprinted, chambered organoid. <span class='html-italic'>Circ. Res.</span> <b>2020</b>, <span class='html-italic'>127</span>, 207–224. [<a href="https://scholar.google.com/scholar_lookup?title=In+situ+expansion,+differentiation,+and+electromechanical+coupling+of+human+cardiac+muscle+in+a+3D+bioprinted,+chambered+organoid&author=Kupfer,+M.E.&author=Lin,+W.H.&author=Ravikumar,+V.&author=Qiu,+K.&author=Wang,+L.&author=Gao,+L.&author=Bhuiyan,+D.B.&author=Lenz,+M.&author=Ai,+J.&author=Mahutga,+R.R.&publication_year=2020&journal=Circ.+Res.&volume=127&pages=207%E2%80%93224&doi=10.1161/CIRCRESAHA.119.316155&pmid=32228120" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1161/CIRCRESAHA.119.316155" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/32228120" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B3-jfb-15-00297' class='html-x' data-content='3.'>MacQueen, L.A.; Sheehy, S.P.; Chantre, C.O.; Zimmerman, J.F.; Pasqualini, F.S.; Liu, X.; Goss, J.A.; Campbell, P.H.; Gonzalez, G.M.; Park, S.J.; et al. A tissue-engineered scale model of the heart ventricle. <span class='html-italic'>Nat. Biomed. Eng.</span> <b>2018</b>, <span class='html-italic'>2</span>, 930–941. [<a href="https://scholar.google.com/scholar_lookup?title=A+tissue-engineered+scale+model+of+the+heart+ventricle&author=MacQueen,+L.A.&author=Sheehy,+S.P.&author=Chantre,+C.O.&author=Zimmerman,+J.F.&author=Pasqualini,+F.S.&author=Liu,+X.&author=Goss,+J.A.&author=Campbell,+P.H.&author=Gonzalez,+G.M.&author=Park,+S.J.&publication_year=2018&journal=Nat.+Biomed.+Eng.&volume=2&pages=930%E2%80%93941&doi=10.1038/s41551-018-0271-5" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1038/s41551-018-0271-5" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B4-jfb-15-00297' class='html-x' data-content='4.'>Jain, T.; Baker, H.B.; Gipsov, A.; Fisher, J.P.; Joy, A.; Kaplan, D.S.; Isayeva, I. Impact of cell density on the bioprinting of gelatin methacrylate (GelMA) bioinks. <span class='html-italic'>Bioprinting</span> <b>2021</b>, <span class='html-italic'>22</span>, e00131. [<a href="https://scholar.google.com/scholar_lookup?title=Impact+of+cell+density+on+the+bioprinting+of+gelatin+methacrylate+(GelMA)+bioinks&author=Jain,+T.&author=Baker,+H.B.&author=Gipsov,+A.&author=Fisher,+J.P.&author=Joy,+A.&author=Kaplan,+D.S.&author=Isayeva,+I.&publication_year=2021&journal=Bioprinting&volume=22&pages=e00131&doi=10.1016/j.bprint.2021.e00131" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.bprint.2021.e00131" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B5-jfb-15-00297' class='html-x' data-content='5.'>Kim, J.S.; Hong, S.; Hwang, C. Bio-ink materials for 3D bio-printing. <span class='html-italic'>J. Int. Soc. Simul. Surg.</span> <b>2016</b>, <span class='html-italic'>3</span>, 49–59. [<a href="https://scholar.google.com/scholar_lookup?title=Bio-ink+materials+for+3D+bio-printing&author=Kim,+J.S.&author=Hong,+S.&author=Hwang,+C.&publication_year=2016&journal=J.+Int.+Soc.+Simul.+Surg.&volume=3&pages=49%E2%80%9359&doi=10.18204/JISSiS.2016.3.2.049" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.18204/JISSiS.2016.3.2.049" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B6-jfb-15-00297' class='html-x' data-content='6.'>Fan, C.; Wang, D.A. Macroporous hydrogel scaffolds for three-dimensional cell culture and tissue engineering. <span class='html-italic'>Tissue Eng. Part B Rev.</span> <b>2017</b>, <span class='html-italic'>23</span>, 451–461. [<a href="https://scholar.google.com/scholar_lookup?title=Macroporous+hydrogel+scaffolds+for+three-dimensional+cell+culture+and+tissue+engineering&author=Fan,+C.&author=Wang,+D.A.&publication_year=2017&journal=Tissue+Eng.+Part+B+Rev.&volume=23&pages=451%E2%80%93461&doi=10.1089/ten.teb.2016.0465" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1089/ten.teb.2016.0465" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B7-jfb-15-00297' class='html-x' data-content='7.'>Iervolino, F.; Belgio, B.; Bonessa, A.; Potere, F.; Suriano, R.; Boschetti, F.; Mantero, S.; Levi, M. Versatile and non-cytotoxic GelMA-xanthan gum biomaterial ink for extrusion-based 3D bioprinting. <span class='html-italic'>Bioprinting</span> <b>2023</b>, <span class='html-italic'>31</span>, e00269. [<a href="https://scholar.google.com/scholar_lookup?title=Versatile+and+non-cytotoxic+GelMA-xanthan+gum+biomaterial+ink+for+extrusion-based+3D+bioprinting&author=Iervolino,+F.&author=Belgio,+B.&author=Bonessa,+A.&author=Potere,+F.&author=Suriano,+R.&author=Boschetti,+F.&author=Mantero,+S.&author=Levi,+M.&publication_year=2023&journal=Bioprinting&volume=31&pages=e00269&doi=10.1016/j.bprint.2023.e00269" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.bprint.2023.e00269" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B8-jfb-15-00297' class='html-x' data-content='8.'>Gao, Q.; Kim, B.S.; Gao, G. Advanced strategies for 3D bioprinting of tissue and organ analogs using alginate hydrogel bioinks. <span class='html-italic'>Mar. Drugs</span> <b>2021</b>, <span class='html-italic'>19</span>, 708. [<a href="https://scholar.google.com/scholar_lookup?title=Advanced+strategies+for+3D+bioprinting+of+tissue+and+organ+analogs+using+alginate+hydrogel+bioinks&author=Gao,+Q.&author=Kim,+B.S.&author=Gao,+G.&publication_year=2021&journal=Mar.+Drugs&volume=19&pages=708&doi=10.3390/md19120708" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.3390/md19120708" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B9-jfb-15-00297' class='html-x' data-content='9.'>Fatimi, A.; Okoro, O.V.; Podstawczyk, D.; Siminska-Stanny, J.; Shavandi, A. Natural Hydrogel-Based Bio-Inks for 3D Bioprinting in Tissue Engineering: A Review. <span class='html-italic'>Gels</span> <b>2022</b>, <span class='html-italic'>8</span>, 179. [<a href="https://scholar.google.com/scholar_lookup?title=Natural+Hydrogel-Based+Bio-Inks+for+3D+Bioprinting+in+Tissue+Engineering:+A+Review&author=Fatimi,+A.&author=Okoro,+O.V.&author=Podstawczyk,+D.&author=Siminska-Stanny,+J.&author=Shavandi,+A.&publication_year=2022&journal=Gels&volume=8&pages=179&doi=10.3390/gels8030179" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.3390/gels8030179" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B10-jfb-15-00297' class='html-xx' data-content='10.'>Liu, W.; Heinrich, M.A.; Zhou, Y.; Akpek, A.; Hu, N.; Liu, X.; Guan, X.; Zhong, Z.; Jin, X.; Khademhosseini, A.; et al. Extrusion bioprinting of shear-thinning gelatin methacryloyl bioinks. <span class='html-italic'>Adv. Healthc. Mater.</span> <b>2017</b>, <span class='html-italic'>6</span>, 1601451. [<a href="https://scholar.google.com/scholar_lookup?title=Extrusion+bioprinting+of+shear-thinning+gelatin+methacryloyl+bioinks&author=Liu,+W.&author=Heinrich,+M.A.&author=Zhou,+Y.&author=Akpek,+A.&author=Hu,+N.&author=Liu,+X.&author=Guan,+X.&author=Zhong,+Z.&author=Jin,+X.&author=Khademhosseini,+A.&publication_year=2017&journal=Adv.+Healthc.+Mater.&volume=6&pages=1601451&doi=10.1002/adhm.201601451" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1002/adhm.201601451" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B11-jfb-15-00297' class='html-xx' data-content='11.'>Skardal, A.; Zhang, J.; Prestwich, G.D. Bioprinting vessel-like constructs using hyaluronan hydrogels crosslinked with tetrahedral polyethylene glycol tetracrylates. <span class='html-italic'>Biomaterials</span> <b>2010</b>, <span class='html-italic'>31</span>, 6173–6181. [<a href="https://scholar.google.com/scholar_lookup?title=Bioprinting+vessel-like+constructs+using+hyaluronan+hydrogels+crosslinked+with+tetrahedral+polyethylene+glycol+tetracrylates&author=Skardal,+A.&author=Zhang,+J.&author=Prestwich,+G.D.&publication_year=2010&journal=Biomaterials&volume=31&pages=6173%E2%80%936181&doi=10.1016/j.biomaterials.2010.04.045&pmid=20546891" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.biomaterials.2010.04.045" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/20546891" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B12-jfb-15-00297' class='html-xx' data-content='12.'>Schöneberg, J.; De Lorenzi, F.; Theek, B.; Blaeser, A.; Rommel, D.; Kuehne, A.J.C.; Kießling, F.; Fischer, H. Engineering biofunctional in vitro vessel models using a multilayer bioprinting technique. <span class='html-italic'>Sci. Rep.</span> <b>2018</b>, <span class='html-italic'>8</span>, 10430. [<a href="https://scholar.google.com/scholar_lookup?title=Engineering+biofunctional+in+vitro+vessel+models+using+a+multilayer+bioprinting+technique&author=Sch%C3%B6neberg,+J.&author=De+Lorenzi,+F.&author=Theek,+B.&author=Blaeser,+A.&author=Rommel,+D.&author=Kuehne,+A.J.C.&author=Kie%C3%9Fling,+F.&author=Fischer,+H.&publication_year=2018&journal=Sci.+Rep.&volume=8&pages=10430&doi=10.1038/s41598-018-28715-0&pmid=29992981" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1038/s41598-018-28715-0" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/29992981" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B13-jfb-15-00297' class='html-xx' data-content='13.'>Leucht, A.; Volz, A.C.; Rogal, J.; Borchers, K.; Kluger, P.J. Advanced gelatin-based vascularization bioinks for extrusion-based bioprinting of vascularized bone equivalents. <span class='html-italic'>Sci. Rep.</span> <b>2020</b>, <span class='html-italic'>10</span>, 5330. [<a href="https://scholar.google.com/scholar_lookup?title=Advanced+gelatin-based+vascularization+bioinks+for+extrusion-based+bioprinting+of+vascularized+bone+equivalents&author=Leucht,+A.&author=Volz,+A.C.&author=Rogal,+J.&author=Borchers,+K.&author=Kluger,+P.J.&publication_year=2020&journal=Sci.+Rep.&volume=10&pages=5330&doi=10.1038/s41598-020-62166-w&pmid=32210309" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1038/s41598-020-62166-w" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/32210309" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B14-jfb-15-00297' class='html-xx' data-content='14.'>Shah, P.P.; Shah, H.B.; Maniar, K.K.; Özel, T. Extrusion-based 3D bioprinting of alginate-based tissue constructs. <span class='html-italic'>Proc. CIRP</span> <b>2020</b>, <span class='html-italic'>95</span>, 143–148. [<a href="https://scholar.google.com/scholar_lookup?title=Extrusion-based+3D+bioprinting+of+alginate-based+tissue+constructs&author=Shah,+P.P.&author=Shah,+H.B.&author=Maniar,+K.K.&author=%C3%96zel,+T.&publication_year=2020&journal=Proc.+CIRP&volume=95&pages=143%E2%80%93148&doi=10.1016/j.procir.2020.06.007" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.procir.2020.06.007" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B15-jfb-15-00297' class='html-xx' data-content='15.'>Hong, S.; Sycks, D.; Chan, H.F.; Lin, S.; Lopez, G.P.; Guilak, F.; Leong, K.W.; Zhao, X. 3D printing of highly stretchable and tough hydrogels into complex, Cellularized structures. <span class='html-italic'>Adv. Mater.</span> <b>2015</b>, <span class='html-italic'>27</span>, 4035. [<a href="https://scholar.google.com/scholar_lookup?title=3D+printing+of+highly+stretchable+and+tough+hydrogels+into+complex,+Cellularized+structures&author=Hong,+S.&author=Sycks,+D.&author=Chan,+H.F.&author=Lin,+S.&author=Lopez,+G.P.&author=Guilak,+F.&author=Leong,+K.W.&author=Zhao,+X.&publication_year=2015&journal=Adv.+Mater.&volume=27&pages=4035&doi=10.1002/adma.201501099" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1002/adma.201501099" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B16-jfb-15-00297' class='html-xx' data-content='16.'>Fu, Z.; Angeline, V.; Sun, W. Evaluation of printing parameters on 3D extrusion printing of pluronic hydrogels and machine learning guided parameter recommendation. <span class='html-italic'>Int. J. Bioprint.</span> <b>2021</b>, <span class='html-italic'>7</span>, 434. [<a href="https://scholar.google.com/scholar_lookup?title=Evaluation+of+printing+parameters+on+3D+extrusion+printing+of+pluronic+hydrogels+and+machine+learning+guided+parameter+recommendation&author=Fu,+Z.&author=Angeline,+V.&author=Sun,+W.&publication_year=2021&journal=Int.+J.+Bioprint.&volume=7&pages=434&doi=10.18063/ijb.v7i4.434" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.18063/ijb.v7i4.434" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B17-jfb-15-00297' class='html-xx' data-content='17.'>Tigner, T.J.; Rajput, S.; Gaharwar, A.K.; Alge, D.L. Comparison of photo cross linkable gelatin derivatives and initiators for three-dimensional extrusion bioprinting. <span class='html-italic'>Biomacromolecules</span> <b>2019</b>, <span class='html-italic'>21</span>, 454–463. [<a href="https://scholar.google.com/scholar_lookup?title=Comparison+of+photo+cross+linkable+gelatin+derivatives+and+initiators+for+three-dimensional+extrusion+bioprinting&author=Tigner,+T.J.&author=Rajput,+S.&author=Gaharwar,+A.K.&author=Alge,+D.L.&publication_year=2019&journal=Biomacromolecules&volume=21&pages=454%E2%80%93463&doi=10.1021/acs.biomac.9b01204" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1021/acs.biomac.9b01204" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B18-jfb-15-00297' class='html-xx' data-content='18.'>Nichol, J.W.; Koshy, S.T.; Bae, H.; Hwang, C.M.; Yamanlar, S.; Khademhosseini, A. Cell-laden microengineered gelatin methacrylate hydrogels. <span class='html-italic'>Biomaterials</span> <b>2010</b>, <span class='html-italic'>31</span>, 5536–5544. [<a href="https://scholar.google.com/scholar_lookup?title=Cell-laden+microengineered+gelatin+methacrylate+hydrogels&author=Nichol,+J.W.&author=Koshy,+S.T.&author=Bae,+H.&author=Hwang,+C.M.&author=Yamanlar,+S.&author=Khademhosseini,+A.&publication_year=2010&journal=Biomaterials&volume=31&pages=5536%E2%80%935544&doi=10.1016/j.biomaterials.2010.03.064" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.biomaterials.2010.03.064" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B19-jfb-15-00297' class='html-xx' data-content='19.'>Lessone, S. Processi di Fotopolimerizzazione per L’ottenimento di un Nanocomposito a Base Cellulosica. Ph.D. Thesis, Politecnico di Torino, Torino, Italy, 2017. [<a href="https://scholar.google.com/scholar_lookup?title=Processi+di+Fotopolimerizzazione+per+L%E2%80%99ottenimento+di+un+Nanocomposito+a+Base+Cellulosica&author=Lessone,+S.&publication_year=2017" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>]</li><li id='B20-jfb-15-00297' class='html-xx' data-content='20.'>Chen, Y.C.; Lin, R.Z.; Qi, H.; Yang, Y.; Bae, H.; Melero-Martin, J.M.; Khademhosseini, A. Functional human vascular network generated in photocrosslinkable gelatin methacrylate hydrogels. <span class='html-italic'>Adv. Funct. Mater.</span> <b>2012</b>, <span class='html-italic'>22</span>, 2027–2039. [<a href="https://scholar.google.com/scholar_lookup?title=Functional+human+vascular+network+generated+in+photocrosslinkable+gelatin+methacrylate+hydrogels&author=Chen,+Y.C.&author=Lin,+R.Z.&author=Qi,+H.&author=Yang,+Y.&author=Bae,+H.&author=Melero-Martin,+J.M.&author=Khademhosseini,+A.&publication_year=2012&journal=Adv.+Funct.+Mater.&volume=22&pages=2027%E2%80%932039&doi=10.1002/adfm.201101662" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1002/adfm.201101662" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B21-jfb-15-00297' class='html-xx' data-content='21.'>Pan, J.; Deng, J.; Yu, L.; Wang, Y.; Zhang, W.; Han, X.; Camargo, P.H.C.; Wang, J.; Liu, Y. Investigating the repair of alveolar bone defects by gelatin methacrylate hydrogels-encapsulated human periodontal ligament stem cells. <span class='html-italic'>J. Mater. Sci. Mater. Med.</span> <b>2020</b>, <span class='html-italic'>31</span>, 1–12. [<a href="https://scholar.google.com/scholar_lookup?title=Investigating+the+repair+of+alveolar+bone+defects+by+gelatin+methacrylate+hydrogels-encapsulated+human+periodontal+ligament+stem+cells&author=Pan,+J.&author=Deng,+J.&author=Yu,+L.&author=Wang,+Y.&author=Zhang,+W.&author=Han,+X.&author=Camargo,+P.H.C.&author=Wang,+J.&author=Liu,+Y.&publication_year=2020&journal=J.+Mater.+Sci.+Mater.+Med.&volume=31&pages=1%E2%80%9312&doi=10.1007/s10856-019-6333-8" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1007/s10856-019-6333-8" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B22-jfb-15-00297' class='html-xx' data-content='22.'>Guimarães, C.F.; Gasperini, L.; Marques, A.P.; Reis, R.L. The stiffness of living tissues and its implications for tissue engineering. <span class='html-italic'>Nat. Rev. Mater.</span> <b>2020</b>, <span class='html-italic'>5</span>, 351–370. [<a href="https://scholar.google.com/scholar_lookup?title=The+stiffness+of+living+tissues+and+its+implications+for+tissue+engineering&author=Guimar%C3%A3es,+C.F.&author=Gasperini,+L.&author=Marques,+A.P.&author=Reis,+R.L.&publication_year=2020&journal=Nat.+Rev.+Mater.&volume=5&pages=351%E2%80%93370&doi=10.1038/s41578-019-0169-1" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1038/s41578-019-0169-1" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B23-jfb-15-00297' class='html-xx' data-content='23.'>Arani, A.; Arunachalam, S.P.; Chang, I.C.; Baffour, F.; Rossman, P.J.; Glaser, K.J.; Trzasko, J.D.; McGee, K.P.; Manduca, A.; Grogan, M.; et al. Cardiac MR elastography for quantitative assessment of elevated myocardial stiffness in cardiac amyloidosis. <span class='html-italic'>J. Magn. Reson. Imaging</span> <b>2017</b>, <span class='html-italic'>46</span>, 1361–1367. [<a href="https://scholar.google.com/scholar_lookup?title=Cardiac+MR+elastography+for+quantitative+assessment+of+elevated+myocardial+stiffness+in+cardiac+amyloidosis&author=Arani,+A.&author=Arunachalam,+S.P.&author=Chang,+I.C.&author=Baffour,+F.&author=Rossman,+P.J.&author=Glaser,+K.J.&author=Trzasko,+J.D.&author=McGee,+K.P.&author=Manduca,+A.&author=Grogan,+M.&publication_year=2017&journal=J.+Magn.+Reson.+Imaging&volume=46&pages=1361%E2%80%931367&doi=10.1002/jmri.25678&pmid=28236336" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1002/jmri.25678" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/28236336" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B24-jfb-15-00297' class='html-xx' data-content='24.'>Bertassoni, L.E.; Cardoso, J.C.; Manoharan, V.; Cristino, A.L.; Bhise, N.S.; Araujo, W.A.; Zorlutuna, P.; Vrana, N.E.; Ghaemmaghami, A.M.; Dokmeci, M.R.; et al. Direct-write bioprinting of cell-laden methacrylated gelatin hydrogels. <span class='html-italic'>Biofabrication</span> <b>2014</b>, <span class='html-italic'>6</span>, 024105. [<a href="https://scholar.google.com/scholar_lookup?title=Direct-write+bioprinting+of+cell-laden+methacrylated+gelatin+hydrogels&author=Bertassoni,+L.E.&author=Cardoso,+J.C.&author=Manoharan,+V.&author=Cristino,+A.L.&author=Bhise,+N.S.&author=Araujo,+W.A.&author=Zorlutuna,+P.&author=Vrana,+N.E.&author=Ghaemmaghami,+A.M.&author=Dokmeci,+M.R.&publication_year=2014&journal=Biofabrication&volume=6&pages=024105&doi=10.1088/1758-5082/6/2/024105&pmid=24695367" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1088/1758-5082/6/2/024105" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/24695367" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B25-jfb-15-00297' class='html-xx' data-content='25.'>Celikkin, N.; Mastrogiacomo, S.; Jaroszewicz, J.; Walboomers, X.F.; Swieszkowski, W. Gelatin methacrylate scaffold for bone tissue engineering: The influence of polymer concentration. <span class='html-italic'>J. Biomed. Mater. Res. A</span> <b>2018</b>, <span class='html-italic'>106</span>, 201–209. [<a href="https://scholar.google.com/scholar_lookup?title=Gelatin+methacrylate+scaffold+for+bone+tissue+engineering:+The+influence+of+polymer+concentration&author=Celikkin,+N.&author=Mastrogiacomo,+S.&author=Jaroszewicz,+J.&author=Walboomers,+X.F.&author=Swieszkowski,+W.&publication_year=2018&journal=J.+Biomed.+Mater.+Res.+A&volume=106&pages=201%E2%80%93209&doi=10.1002/jbm.a.36226" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1002/jbm.a.36226" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B26-jfb-15-00297' class='html-xx' data-content='26.'>Pepelanova, I.; Kruppa, K.; Scheper, T.; Lavrentieva, A. Gelatin-methacryloyl (GelMA) hydrogels with defined degree of functionalization as a versatile toolkit for 3D cell culture and extrusion bioprinting. <span class='html-italic'>Bioengineering</span> <b>2018</b>, <span class='html-italic'>5</span>, 55. [<a href="https://scholar.google.com/scholar_lookup?title=Gelatin-methacryloyl+(GelMA)+hydrogels+with+defined+degree+of+functionalization+as+a+versatile+toolkit+for+3D+cell+culture+and+extrusion+bioprinting&author=Pepelanova,+I.&author=Kruppa,+K.&author=Scheper,+T.&author=Lavrentieva,+A.&publication_year=2018&journal=Bioengineering&volume=5&pages=55&doi=10.3390/bioengineering5030055" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.3390/bioengineering5030055" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B27-jfb-15-00297' class='html-xx' data-content='27.'>Shie, M.Y.; Lee, J.J.; Ho, C.C.; Yen, S.Y.; Ng, H.Y.; Chen, Y.W. Effects of gelatin methacrylate bio-ink concentration on mechano-physical properties and human dermal fibroblast behavior. <span class='html-italic'>Polymers</span> <b>2020</b>, <span class='html-italic'>12</span>, 1930. [<a href="https://scholar.google.com/scholar_lookup?title=Effects+of+gelatin+methacrylate+bio-ink+concentration+on+mechano-physical+properties+and+human+dermal+fibroblast+behavior&author=Shie,+M.Y.&author=Lee,+J.J.&author=Ho,+C.C.&author=Yen,+S.Y.&author=Ng,+H.Y.&author=Chen,+Y.W.&publication_year=2020&journal=Polymers&volume=12&pages=1930&doi=10.3390/polym12091930" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.3390/polym12091930" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B28-jfb-15-00297' class='html-xx' data-content='28.'>Yin, J.; Yan, M.; Wang, Y.; Fu, J.; Suo, H. 3D bioprinting of low-concentration cell-laden gelatin methacrylate (GelMA) bioinks with a two-step cross-linking strategy. <span class='html-italic'>ACS Appl. Mater. Interfaces</span> <b>2018</b>, <span class='html-italic'>10</span>, 6849–6857. [<a href="https://scholar.google.com/scholar_lookup?title=3D+bioprinting+of+low-concentration+cell-laden+gelatin+methacrylate+(GelMA)+bioinks+with+a+two-step+cross-linking+strategy&author=Yin,+J.&author=Yan,+M.&author=Wang,+Y.&author=Fu,+J.&author=Suo,+H.&publication_year=2018&journal=ACS+Appl.+Mater.+Interfaces&volume=10&pages=6849%E2%80%936857&doi=10.1021/acsami.7b16059" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1021/acsami.7b16059" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B29-jfb-15-00297' class='html-xx' data-content='29.'>Xu, P.; Guan, J.; Chen, Y.; Xiao, H.; Yang, T.; Sun, H.; Wu, N.; Zhang, C.; Mao, Y. Stiffness of photocrosslinkable gelatin hydrogel influences nucleus pulposus cell propertiesin vitro. <span class='html-italic'>J. Cell. Mol. Med.</span> <b>2020</b>, <span class='html-italic'>25</span>, 880–891. [<a href="https://scholar.google.com/scholar_lookup?title=Stiffness+of+photocrosslinkable+gelatin+hydrogel+influences+nucleus+pulposus+cell+propertiesin+vitro&author=Xu,+P.&author=Guan,+J.&author=Chen,+Y.&author=Xiao,+H.&author=Yang,+T.&author=Sun,+H.&author=Wu,+N.&author=Zhang,+C.&author=Mao,+Y.&publication_year=2020&journal=J.+Cell.+Mol.+Med.&volume=25&pages=880%E2%80%93891&doi=10.1111/jcmm.16141" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1111/jcmm.16141" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B30-jfb-15-00297' class='html-xx' data-content='30.'>Wei, K.; Sun, J.; Gao, Q.; Yang, X.; Ye, Y.; Ji, J.; Sun, X. 3D “honeycomb” cell/carbon nanofiber/gelatin methacryloyl (GelMA) modified screen-printed electrode for electrochemical assessment of the combined toxicity of deoxynivalenol family mycotoxins. <span class='html-italic'>Bioelectrochemistry</span> <b>2021</b>, <span class='html-italic'>139</span>, 107743. [<a href="https://scholar.google.com/scholar_lookup?title=3D+%E2%80%9Choneycomb%E2%80%9D+cell/carbon+nanofiber/gelatin+methacryloyl+(GelMA)+modified+screen-printed+electrode+for+electrochemical+assessment+of+the+combined+toxicity+of+deoxynivalenol+family+mycotoxins&author=Wei,+K.&author=Sun,+J.&author=Gao,+Q.&author=Yang,+X.&author=Ye,+Y.&author=Ji,+J.&author=Sun,+X.&publication_year=2021&journal=Bioelectrochemistry&volume=139&pages=107743&doi=10.1016/j.bioelechem.2021.107743" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.bioelechem.2021.107743" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B31-jfb-15-00297' class='html-xx' data-content='31.'>Li, J.; Moeinzadeh, S.; Kim, C.; Pan, C.C.; Weale, G.; Kim, S.; Abrams, G.; James, A.W.; Choo, H.; Chan, C.; et al. Development and systematic characterization of GelMA/alginate/PEGDMA/xanthan gum hydrogel bioink system for extrusion bioprinting. <span class='html-italic'>Biomaterials</span> <b>2023</b>, <span class='html-italic'>293</span>, 121969. [<a href="https://scholar.google.com/scholar_lookup?title=Development+and+systematic+characterization+of+GelMA/alginate/PEGDMA/xanthan+gum+hydrogel+bioink+system+for+extrusion+bioprinting&author=Li,+J.&author=Moeinzadeh,+S.&author=Kim,+C.&author=Pan,+C.C.&author=Weale,+G.&author=Kim,+S.&author=Abrams,+G.&author=James,+A.W.&author=Choo,+H.&author=Chan,+C.&publication_year=2023&journal=Biomaterials&volume=293&pages=121969&doi=10.1016/j.biomaterials.2022.121969" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.biomaterials.2022.121969" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B32-jfb-15-00297' class='html-xx' data-content='32.'>Martyniak, K.; Lokshina, A.; Cruz, M.A.; Karimzadeh, M.; Kemp, R.; Kean, T.J. Biomaterial composition and stiffness as decisive properties of 3D bioprinted constructs for type II collagen stimulation. <span class='html-italic'>Acta Biomater.</span> <b>2022</b>, <span class='html-italic'>152</span>, 221–234. [<a href="https://scholar.google.com/scholar_lookup?title=Biomaterial+composition+and+stiffness+as+decisive+properties+of+3D+bioprinted+constructs+for+type+II+collagen+stimulation&author=Martyniak,+K.&author=Lokshina,+A.&author=Cruz,+M.A.&author=Karimzadeh,+M.&author=Kemp,+R.&author=Kean,+T.J.&publication_year=2022&journal=Acta+Biomater.&volume=152&pages=221%E2%80%93234&doi=10.1016/j.actbio.2022.08.058&pmid=36049623" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.actbio.2022.08.058" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/36049623" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B33-jfb-15-00297' class='html-xx' data-content='33.'>Di Giuseppe, M.; Law, N.; Webb, B.; Macrae, R.A.; Liew, L.J.; Sercombe, T.B.; Dilley, R.J.; Doyle, B.J. Mechanical behaviour of alginate-gelatin hydrogels for 3D bioprinting. <span class='html-italic'>J. Mech. Behav. Biomed. Mater.</span> <b>2018</b>, <span class='html-italic'>79</span>, 150–157. [<a href="https://scholar.google.com/scholar_lookup?title=Mechanical+behaviour+of+alginate-gelatin+hydrogels+for+3D+bioprinting&author=Di+Giuseppe,+M.&author=Law,+N.&author=Webb,+B.&author=Macrae,+R.A.&author=Liew,+L.J.&author=Sercombe,+T.B.&author=Dilley,+R.J.&author=Doyle,+B.J.&publication_year=2018&journal=J.+Mech.+Behav.+Biomed.+Mater.&volume=79&pages=150%E2%80%93157&doi=10.1016/j.jmbbm.2017.12.018&pmid=29304429" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.jmbbm.2017.12.018" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/29304429" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B34-jfb-15-00297' class='html-xx' data-content='34.'>Ouyang, L.; Yao, R.; Zhao, Y.; Sun, W. Effect of bioink properties on printability and cell viability for 3D bioplotting of embryonic stem cells. <span class='html-italic'>Biofabrication</span> <b>2016</b>, <span class='html-italic'>8</span>, 035020. [<a href="https://scholar.google.com/scholar_lookup?title=Effect+of+bioink+properties+on+printability+and+cell+viability+for+3D+bioplotting+of+embryonic+stem+cells&author=Ouyang,+L.&author=Yao,+R.&author=Zhao,+Y.&author=Sun,+W.&publication_year=2016&journal=Biofabrication&volume=8&pages=035020&doi=10.1088/1758-5090/8/3/035020&pmid=27634915" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1088/1758-5090/8/3/035020" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>] [<a href="https://www.ncbi.nlm.nih.gov/pubmed/27634915" class='cross-ref pub_med' data-typ='pmid' target='_blank' rel='noopener noreferrer'>PubMed</a>]</li><li id='B35-jfb-15-00297' class='html-xx' data-content='35.'>Zhu, W.; Qu, X.; Zhu, J.; Ma, X.; Patel, S.; Liu, J.; Wang, P.; Lai, C.S.; Gou, M.; Xu, Y.; et al. Direct 3D bioprinting of prevascularized tissue constructs with complex microarchitecture. <span class='html-italic'>Biomaterials</span> <b>2017</b>, <span class='html-italic'>124</span>, 106–115. [<a href="https://scholar.google.com/scholar_lookup?title=Direct+3D+bioprinting+of+prevascularized+tissue+constructs+with+complex+microarchitecture&author=Zhu,+W.&author=Qu,+X.&author=Zhu,+J.&author=Ma,+X.&author=Patel,+S.&author=Liu,+J.&author=Wang,+P.&author=Lai,+C.S.&author=Gou,+M.&author=Xu,+Y.&publication_year=2017&journal=Biomaterials&volume=124&pages=106%E2%80%93115&doi=10.1016/j.biomaterials.2017.01.042" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.biomaterials.2017.01.042" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B36-jfb-15-00297' class='html-xx' data-content='36.'>Semba, J.A.; Mieloch, A.A.; Tomaszewska, E.; Cywoniuk, P.; Rybka, J.D. Formulation and evaluation of a bioink composed of alginate, gelatin, and nanocellulose for meniscal tissue engineering. <span class='html-italic'>Int. J. Bioprint.</span> <b>2022</b>, <span class='html-italic'>9</span>, 621. [<a href="https://scholar.google.com/scholar_lookup?title=Formulation+and+evaluation+of+a+bioink+composed+of+alginate,+gelatin,+and+nanocellulose+for+meniscal+tissue+engineering&author=Semba,+J.A.&author=Mieloch,+A.A.&author=Tomaszewska,+E.&author=Cywoniuk,+P.&author=Rybka,+J.D.&publication_year=2022&journal=Int.+J.+Bioprint.&volume=9&pages=621&doi=10.18063/ijb.v9i1.621" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.18063/ijb.v9i1.621" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B37-jfb-15-00297' class='html-xx' data-content='37.'>Bedada, F.B.; Chan, S.S.; Metzger, S.K.; Zhang, L.; Zhang, J.; Garry, D.J.; Kamp, T.J.; Kyba, M.; Metzger, J.M. Acquisition of a quantitative, stoichiometrically conserved ratiometric marker of maturation status in stem cell-derived cardiac myocytes. <span class='html-italic'>Stem. Cell Rep.</span> <b>2014</b>, <span class='html-italic'>3</span>, 594–605. [<a href="https://scholar.google.com/scholar_lookup?title=Acquisition+of+a+quantitative,+stoichiometrically+conserved+ratiometric+marker+of+maturation+status+in+stem+cell-derived+cardiac+myocytes&author=Bedada,+F.B.&author=Chan,+S.S.&author=Metzger,+S.K.&author=Zhang,+L.&author=Zhang,+J.&author=Garry,+D.J.&author=Kamp,+T.J.&author=Kyba,+M.&author=Metzger,+J.M.&publication_year=2014&journal=Stem.+Cell+Rep.&volume=3&pages=594%E2%80%93605&doi=10.1016/j.stemcr.2014.07.012" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.stemcr.2014.07.012" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B38-jfb-15-00297' class='html-xx' data-content='38.'>Pioner, J.M.; Vitale, G.; Steczina, S.; Langione, M.; Margara, F.; Santini, L.; Giardini, F.; Lazzeri, E.; Piroddi, N.; Scellini, B.; et al. Slower calcium handling balances faster cross-bridge cycling in human MYBPC3 HCM. <span class='html-italic'>Circ. Res.</span> <b>2023</b>, <span class='html-italic'>132</span>, 628–644. [<a href="https://scholar.google.com/scholar_lookup?title=Slower+calcium+handling+balances+faster+cross-bridge+cycling+in+human+MYBPC3+HCM&author=Pioner,+J.M.&author=Vitale,+G.&author=Steczina,+S.&author=Langione,+M.&author=Margara,+F.&author=Santini,+L.&author=Giardini,+F.&author=Lazzeri,+E.&author=Piroddi,+N.&author=Scellini,+B.&publication_year=2023&journal=Circ.+Res.&volume=132&pages=628%E2%80%93644&doi=10.1161/CIRCRESAHA.122.321956" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1161/CIRCRESAHA.122.321956" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B39-jfb-15-00297' class='html-xx' data-content='39.'>Doss, M.X.; Di Diego, J.M.; Goodrow, R.J.; Wu, Y.; Cordeiro, J.M.; Nesterenko, V.V.; Barajas-Martínez, H.; Hu, D.; Urrutia, J.; Desai, M.; et al. Maximum diastolic potential of human induced pluripotent stem cell-derived cardiomyocytes depends critically on IKr. <span class='html-italic'>PLoS ONE</span> <b>2012</b>, <span class='html-italic'>7</span>, e40288. [<a href="https://scholar.google.com/scholar_lookup?title=Maximum+diastolic+potential+of+human+induced+pluripotent+stem+cell-derived+cardiomyocytes+depends+critically+on+IKr&author=Doss,+M.X.&author=Di+Diego,+J.M.&author=Goodrow,+R.J.&author=Wu,+Y.&author=Cordeiro,+J.M.&author=Nesterenko,+V.V.&author=Barajas-Mart%C3%ADnez,+H.&author=Hu,+D.&author=Urrutia,+J.&author=Desai,+M.&publication_year=2012&journal=PLoS+ONE&volume=7&pages=e40288&doi=10.1371/journal.pone.0040288" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1371/journal.pone.0040288" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B40-jfb-15-00297' class='html-xx' data-content='40.'>Pioner, J.M.; Santini, L.; Palandri, C.; Martella, D.; Lupi, F.; Langione, M.; Querceto, S.; Grandinetti, B.; Balducci, V.; Benzoni, P.; et al. Optical investigation of action potential and calcium handling maturation of hiPSC-cardiomyocytes on biomimetic substrates. <span class='html-italic'>Int. J. Mol. Sci.</span> <b>2019</b>, <span class='html-italic'>20</span>, 3799. [<a href="https://scholar.google.com/scholar_lookup?title=Optical+investigation+of+action+potential+and+calcium+handling+maturation+of+hiPSC-cardiomyocytes+on+biomimetic+substrates&author=Pioner,+J.M.&author=Santini,+L.&author=Palandri,+C.&author=Martella,+D.&author=Lupi,+F.&author=Langione,+M.&author=Querceto,+S.&author=Grandinetti,+B.&author=Balducci,+V.&author=Benzoni,+P.&publication_year=2019&journal=Int.+J.+Mol.+Sci.&volume=20&pages=3799&doi=10.3390/ijms20153799" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.3390/ijms20153799" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B41-jfb-15-00297' class='html-xx' data-content='41.'>Coppini, R.; Ferrantini, C.; Yao, L.; Fan, P.; Del Lungo, M.; Stillitano, F.; Sartiani, L.; Tosi, B.; Suffredini, S.; Tesi, C.; et al. Late sodium current inhibition reverses electromechanical dysfunction in human hypertrophic cardiomyopathy. <span class='html-italic'>Circulation</span> <b>2012</b>, <span class='html-italic'>127</span>, 575–584. [<a href="https://scholar.google.com/scholar_lookup?title=Late+sodium+current+inhibition+reverses+electromechanical+dysfunction+in+human+hypertrophic+cardiomyopathy&author=Coppini,+R.&author=Ferrantini,+C.&author=Yao,+L.&author=Fan,+P.&author=Del+Lungo,+M.&author=Stillitano,+F.&author=Sartiani,+L.&author=Tosi,+B.&author=Suffredini,+S.&author=Tesi,+C.&publication_year=2012&journal=Circulation&volume=127&pages=575%E2%80%93584&doi=10.1161/CIRCULATIONAHA.112.134932" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1161/CIRCULATIONAHA.112.134932" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B42-jfb-15-00297' class='html-xx' data-content='42.'>Goversen, B.; van der Heyden, M.A.; van Veen, T.A.; de Boer, T.P. The immature electrophysiological phenotype of iPSC-CMs still hampers in vitro drug screening: Special focus on IK1. <span class='html-italic'>Pharmacol. Ther.</span> <b>2018</b>, <span class='html-italic'>183</span>, 127–136. [<a href="https://scholar.google.com/scholar_lookup?title=The+immature+electrophysiological+phenotype+of+iPSC-CMs+still+hampers+in+vitro+drug+screening:+Special+focus+on+IK1&author=Goversen,+B.&author=van+der+Heyden,+M.A.&author=van+Veen,+T.A.&author=de+Boer,+T.P.&publication_year=2018&journal=Pharmacol.+Ther.&volume=183&pages=127%E2%80%93136&doi=10.1016/j.pharmthera.2017.10.001" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.pharmthera.2017.10.001" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li><li id='B43-jfb-15-00297' class='html-xx' data-content='43.'>Moreau, A.; Mercier, A.; Thériault, O.; Boutjdir, M.; Burger, B.; Keller, D.I.; Chahine, M. Biophysical, molecular, and pharmacological characterization of voltage-dependent sodium channels from induced pluripotent stem cell-derived cardiomyocytes. <span class='html-italic'>Can. J. Cardiol.</span> <b>2017</b>, <span class='html-italic'>33</span>, 269–278. [<a href="https://scholar.google.com/scholar_lookup?title=Biophysical,+molecular,+and+pharmacological+characterization+of+voltage-dependent+sodium+channels+from+induced+pluripotent+stem+cell-derived+cardiomyocytes&author=Moreau,+A.&author=Mercier,+A.&author=Th%C3%A9riault,+O.&author=Boutjdir,+M.&author=Burger,+B.&author=Keller,+D.I.&author=Chahine,+M.&publication_year=2017&journal=Can.+J.+Cardiol.&volume=33&pages=269%E2%80%93278&doi=10.1016/j.cjca.2016.10.001" class='google-scholar' target='_blank' rel='noopener noreferrer'>Google Scholar</a>] [<a href="https://doi.org/10.1016/j.cjca.2016.10.001" class='cross-ref' target='_blank' rel='noopener noreferrer'>CrossRef</a>]</li></ol></section><section id='Figures' type='display-objects'><div class="html-fig-wrap" id="jfb-15-00297-f001"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f001"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g001.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g001.png" alt="Jfb 15 00297 g001" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g001-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f001"></a> </div> </div> <div class="html-fig_description"> <b>Figure 1.</b> Swelling ratio as a function of time for the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among four samples. A Wilcoxon–Mann–Whitney test indicated a statistically non-significant difference between the GelMA and GelMA-XG series of data (<span class='html-italic'>p</span> = 0.2975).  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f001"> <div class="html-caption"> <b>Figure 1.</b> Swelling ratio as a function of time for the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among four samples. A Wilcoxon–Mann–Whitney test indicated a statistically non-significant difference between the GelMA and GelMA-XG series of data (<span class='html-italic'>p</span> = 0.2975).</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g001.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g001.png" alt="Jfb 15 00297 g001" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g001.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f002"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f002"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g002.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g002.png" alt="Jfb 15 00297 g002" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g002-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f002"></a> </div> </div> <div class="html-fig_description"> <b>Figure 2.</b> Stress-relative indentation curves of the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among four samples. A Wilcoxon–Mann–Whitney test indicated a statistically significant difference between the GelMA and GelMA-XG series of data (<span class='html-italic'>p</span> = 0.0001942).  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f002"> <div class="html-caption"> <b>Figure 2.</b> Stress-relative indentation curves of the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among four samples. A Wilcoxon–Mann–Whitney test indicated a statistically significant difference between the GelMA and GelMA-XG series of data (<span class='html-italic'>p</span> = 0.0001942).</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g002.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g002.png" alt="Jfb 15 00297 g002" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g002.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f003"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f003"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g003.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g003.png" alt="Jfb 15 00297 g003" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g003-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f003"></a> </div> </div> <div class="html-fig_description"> <b>Figure 3.</b> Degradation ratio as a function of time for the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among two samples. A Wilcoxon–Mann–Whitney test indicated a statistically non-significant difference between the GelMA and GelMA-XG series of data (<span class='html-italic'>p</span> = 0.3624).  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f003"> <div class="html-caption"> <b>Figure 3.</b> Degradation ratio as a function of time for the GelMA and GelMA-XG hydrogels. The error bars represent the standard deviation among two samples. A Wilcoxon–Mann–Whitney test indicated a statistically non-significant difference between the GelMA and GelMA-XG series of data (<span class='html-italic'>p</span> = 0.3624).</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g003.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g003.png" alt="Jfb 15 00297 g003" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g003.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f004"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f004"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g004.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g004.png" alt="Jfb 15 00297 g004" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g004-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f004"></a> </div> </div> <div class="html-fig_description"> <b>Figure 4.</b> Example of a structure 3D printed with the GelMA-XG hydrogel.  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f004"> <div class="html-caption"> <b>Figure 4.</b> Example of a structure 3D printed with the GelMA-XG hydrogel.</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g004.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g004.png" alt="Jfb 15 00297 g004" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g004.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f005"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f005"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g005.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g005.png" alt="Jfb 15 00297 g005" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g005-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f005"></a> </div> </div> <div class="html-fig_description"> <b>Figure 5.</b> Assessment of the quality of the extrudable constructs made of the GelMA-XG hydrogel: (<b>A</b>) square frame and example of a 3D-printed version, used to quantify the printing accuracy; (<b>B</b>) grid of square pores and example of a 3D-printed version, used to quantify the printability; zoomed-in views on the right-hand side panel show detailed areas (1, 2, 3) of the printed grid.  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f005"> <div class="html-caption"> <b>Figure 5.</b> Assessment of the quality of the extrudable constructs made of the GelMA-XG hydrogel: (<b>A</b>) square frame and example of a 3D-printed version, used to quantify the printing accuracy; (<b>B</b>) grid of square pores and example of a 3D-printed version, used to quantify the printability; zoomed-in views on the right-hand side panel show detailed areas (1, 2, 3) of the printed grid.</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g005.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g005.png" alt="Jfb 15 00297 g005" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g005.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f006"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f006"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g006.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g006.png" alt="Jfb 15 00297 g006" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g006-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f006"></a> </div> </div> <div class="html-fig_description"> <b>Figure 6.</b> Optical microscopy images of hiPSCs within 2D cell cultures on top of layers of the GelMA-XG, GelMA, GelMA-XG-FN and GelMA-FN hydrogels, taken after 4 and 9 days from seeding.  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f006"> <div class="html-caption"> <b>Figure 6.</b> Optical microscopy images of hiPSCs within 2D cell cultures on top of layers of the GelMA-XG, GelMA, GelMA-XG-FN and GelMA-FN hydrogels, taken after 4 and 9 days from seeding.</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g006.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g006.png" alt="Jfb 15 00297 g006" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g006.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f007"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f007"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g007.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g007.png" alt="Jfb 15 00297 g007" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g007-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f007"></a> </div> </div> <div class="html-fig_description"> <b>Figure 7.</b> Optical microscopy images of hiPSCs within 3D cell cultures inside hydrogel hemispheres made of GelMA-XG and GelMA-XG-FN. The images were taken after 2 and 7 days from UV cross-linking for 15 s, which occurred above a substrate maintained at a temperature of 25 °C or 15 °C.  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f007"> <div class="html-caption"> <b>Figure 7.</b> Optical microscopy images of hiPSCs within 3D cell cultures inside hydrogel hemispheres made of GelMA-XG and GelMA-XG-FN. The images were taken after 2 and 7 days from UV cross-linking for 15 s, which occurred above a substrate maintained at a temperature of 25 °C or 15 °C.</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g007.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g007.png" alt="Jfb 15 00297 g007" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g007.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f008"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f008"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g008.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g008.png" alt="Jfb 15 00297 g008" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g008-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f008"></a> </div> </div> <div class="html-fig_description"> <b>Figure 8.</b> Fluorescence microscopy images of the GelMA-XG hydrogel hemispheres containing differentiated hiPSC cardiomyocytes at day 8 of the differentiation process. The differentiation is indicated by the endogenous expression of the mEGFP fluorescent marker. See the videos in the <a href="#app1-jfb-15-00297" class="html-app">Supplementary Materials</a> which show specimens contracting at a frequency of ~0.8 Hz (highest value recorded).  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f008"> <div class="html-caption"> <b>Figure 8.</b> Fluorescence microscopy images of the GelMA-XG hydrogel hemispheres containing differentiated hiPSC cardiomyocytes at day 8 of the differentiation process. The differentiation is indicated by the endogenous expression of the mEGFP fluorescent marker. See the videos in the <a href="#app1-jfb-15-00297" class="html-app">Supplementary Materials</a> which show specimens contracting at a frequency of ~0.8 Hz (highest value recorded).</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g008.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g008.png" alt="Jfb 15 00297 g008" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g008.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f009"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f009"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g009.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g009.png" alt="Jfb 15 00297 g009" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g009-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f009"></a> </div> </div> <div class="html-fig_description"> <b>Figure 9.</b> Action potential duration at 90% repolarisation of the differentiated cardiomyocytes inside the GelMA-XG hydrogel hemispheres, on day 17 of the differentiation process, in response to an electrical stimulation at 0.5 Hz or 1 Hz, at 37 °C. The error bars represent the standard deviation among three samples.  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f009"> <div class="html-caption"> <b>Figure 9.</b> Action potential duration at 90% repolarisation of the differentiated cardiomyocytes inside the GelMA-XG hydrogel hemispheres, on day 17 of the differentiation process, in response to an electrical stimulation at 0.5 Hz or 1 Hz, at 37 °C. The error bars represent the standard deviation among three samples.</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g009.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g009.png" alt="Jfb 15 00297 g009" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g009.png" /></div> </div> <div class="html-fig-wrap" id="jfb-15-00297-f010"> <div class='html-fig_img'> <div class="html-figpopup html-figpopup-link" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f010"> <img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g010.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g010.png" alt="Jfb 15 00297 g010" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g010-550.jpg" /> <a class="html-expand html-figpopup" data-counterslinkmanual = "https://www.mdpi.com/2079-4983/15/10/297/display" href="#fig_body_display_jfb-15-00297-f010"></a> </div> </div> <div class="html-fig_description"> <b>Figure 10.</b> Optical microscopy images of 3D-printed structures made of the hiPSC-laden GelMA-XG hydrogel.  </div> </div> <div class="html-fig_show mfp-hide" id="fig_body_display_jfb-15-00297-f010"> <div class="html-caption"> <b>Figure 10.</b> Optical microscopy images of 3D-printed structures made of the hiPSC-laden GelMA-XG hydrogel.</div> <div class="html-img"><img data-large="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g010.png" data-original="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g010.png" alt="Jfb 15 00297 g010" data-lsrc="/jfb/jfb-15-00297/article_deploy/html/images/jfb-15-00297-g010.png" /></div> </div> </section><section class='html-fn_group'><table><tr id=''><td></td><td><div class='html-p'><b>Disclaimer/Publisher’s Note:</b> The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.</div></td></tr></table></section> <section id="html-copyright"><br>© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (<a href="https://creativecommons.org/licenses/by/4.0/" target="_blank" rel="noopener noreferrer">https://creativecommons.org/licenses/by/4.0/</a>).</section> </div> </div> <div class="additional-content"> <h2><a name="cite"></a>Share and Cite</h2> <div class="social-media-links" style="text-align: left;"> <a href="/cdn-cgi/l/email-protection#6d524b0c001d561e180f07080e19502b1f0200485f5d20293d24485e2c485f5d485f5f5e29403d1f0403190c0f0108485f5d2a08010c190403485f5d200819050c0e1f14010c190840350c0319050c03485f5d2a1800485f5d2514091f020a0801485f5d2f0402040306485f5d28030c0f0104030a485f5d2518000c03485f5d240309180e0809485f5d3d01181f041d0219080319485f5d3e190800485f5d2e080101485f5d29040b0b081f080319040c19040203485f5d04031902485f5d2e0c1f0904020014020e1419081e4b1c180219564b0c001d560f020914500519191d1e5742421a1a1a4300091d04430e0200425f5455585e5a55485e2c485d2c485d2c5e29403d1f0403190c0f0108485f5d2a08010c190403485f5d200819050c0e1f14010c190840350c0319050c03485f5d2a1800485f5d2514091f020a0801485f5d2f0402040306485f5d28030c0f0104030a485f5d2518000c03485f5d240309180e0809485f5d3d01181f041d0219080319485f5d3e190800485f5d2e080101485f5d29040b0b081f080319040c19040203485f5d04031902485f5d2e0c1f0904020014020e1419081e485d2c485d2c2c0f1e191f0c0e19485e2c485f5d3a08485f5d09081e0e1f040f08485f5d190508485f5d09081b0801021d00080319485f5d020b485f5d0c485f5d0f0402040306485f5d1902485f5d0f04021d1f040319485f5d0518000c03485f5d040309180e0809485f5d1d01181f041d0219080319485f5d1e190800485f5d0e0801011e485f5d485f5505043d3e2e1e485f54485f5d0b021f485f5d1d021e1e040f0108485f5d0e0c1f09040c0e485f5d19041e1e1808485f5d08030a040308081f04030a485f5d181e04030a485f5d0c485f5d0a08010c190403485f5d000819050c0e1f14010c1908485f5d485f552a0801202c485f54400f0c1e0809485f5d0514091f020a080143485f5d3a05040108485f5d1d1f081b0402181e485f5d1e19180904081e485f5d050c1b08485f5d1e05021a03485f5d19050c19485f5d2a0801202c485f5d0c19485f5d0c485f5d01021a485f5d0e02030e0803191f0c19040203485f5d485f5558485f58485f5d1a485f2b1b485f54485f5d0c0101021a1e485f5d0b021f485f5d190508485f5d0a1f021a1905485f5d020b485f5d09041b081f1e08485f5d0e0801011e485f2e485f5d04191e485f5d5e29485f5d1d1f0403190c0f0401041914485f5d050c1e485f5d0f080803485f5d0b02180309485f5d1902485f5d0f08485f5d01040004190809485f5d0f14485f5d04191e485f5d01021a485f5d1b041e0e021e04191443485f5d3902485f5d021b081f0e020008485f5d19050c19485f5d091f0c1a0f0c0e06485f2e485f5d000c0604030a485f5d190508485f5d0514091f020a0801485f5d0f021905485f5d0e02001d0c19040f0108485f5d1a041905485f5d05043d3e2e1e485f5d0c0309485f5d5e29401d1f0403190c0f0108485f2e485f5d1a08485f5d09081b0801021d0809485f5d0c03485f5d0815191f18090c0f0108485f5d2a0801202c400f0c1e0809485f5d0f0402040306485f5d0f14485f5d0c090904030a485f5d150c0319050c03485f5d0a1800485f5d485f55352a485f5443485f5d390508485f5d2a0801202c40352a485f5d0e02001d021e041908485f5d0514091f020a0801485f5d050c09485f5d0c03485f5d08010c1e19040e485f5d0002091801181e485f5d485f551354485f5d063d0c485f54485f5d0e02001d0c1f0c0f0108485f5d1902485f5d19050c19485f5d020b485f5d0e0c1f09040c0e485f5d19041e1e1808485f2e485f5d0c0309485f5d08030c0f010809485f5d5e29485f5d1d1f04031904030a485f5d1a041905485f5d05040a05485f5d1b0c0118081e485f5d020b485f5d1d1f04031904030a485f5d0c0e0e181f0c0e14485f5d485f55555e485f58485f54485f5d0c0309485f5d1d1f0403190c0f0401041914485f5d485f555d435455485f5443485f5d39081e191e485f5d1a041905485f5d05043d3e2e1e485f5d1e05021a0809485f5d190508485f5d0514091f020a0801485f5b1f1e1c1802485e2f1e485f5d0c0f0401041914485f5d1902485f5d1d1f0200021908485f5d190508041f485f5d1d1f0201040b081f0c19040203485f5d1a0419050403485f5d0f021905485f5d5f29485f5d0c0309485f5d5e29485f5d0e080101485f5d0e180119181f081e43485f5d390508485f5d19081e191e485f5d0c011e02485f5d1e05021a0809485f5d19050c19485f5d05043d3e2e1e485f5d04031e040908485f5d050800041e1d05081f081e485f5d020b485f5d190508485f5d0514091f020a0801485f5d1a081f08485f5d0c0f0108485f5d1902485f5d09040b0b081f080319040c1908485f5d04031902485f5d0e0c1f0904020014020e1419081e485f2e485f5d0e0c1d0c0f0108485f5d020b485f5d1e1d0203190c030802181e485f5d0e0203191f0c0e190402031e485f5d485f550c1b081f0c0a08485f5d0b1f081c1808030e14485f5d020b485f5d135d4358485f5d2517485f5d0c0309485f5d0c001d010419180908485f5d020b485f5d135f485f58485f5443485f5d2b181f1905081f00021f08485f2e485f5d0f04021d1f04031904030a485f5d19081e191e485f5d1d1f021b0809485f5d1905083643434330" title="Email"> <i class="fa fa-envelope-square" style="font-size: 30px;"></i> </a> <a href="https://twitter.com/intent/tweet?text=3D-Printable+Gelatin+Methacrylate-Xanthan+Gum+Hydrogel+Bioink+Enabling+Human+Induced+Pluripotent+Stem+Cell+Differentiation+into+Cardiomyocytes&hashtags=mdpijfb&url=https%3A%2F%2Fwww.mdpi.com%2F2985378&via=JFB_MDPI" onclick="windowOpen(this.href,600,800); return false" target="_blank" rel="noopener noreferrer"> <i class="fa fa-twitter-x-square" style="font-size: 30px;"></i> </a> <a href=" http://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fwww.mdpi.com%2F2985378&title=3D-Printable%20Gelatin%20Methacrylate-Xanthan%20Gum%20Hydrogel%20Bioink%20Enabling%20Human%20Induced%20Pluripotent%20Stem%20Cell%20Differentiation%20into%20Cardiomyocytes%26source%3Dhttps%3A%2F%2Fwww.mdpi.com%26summary%3DWe%20describe%20the%20development%20of%20a%20bioink%20to%20bioprint%20human%20induced%20pluripotent%20stem%20cells%20%28hiPSCs%29%20for%20possible%20cardiac%20tissue%20engineering%20using%20a%20gelatin%20methacrylate%20%28GelMA%29-based%20hydrogel.%20While%20previous%20studies%20have%20shown%20that%20GelMA%20at%20a%20low%20%5B...%5D" onclick="windowOpen(this.href,600,800); return false" title="LinkedIn" target="_blank" rel="noopener noreferrer"> <i class="fa fa-linkedin-square" style="font-size: 30px;"></i> </a> <a href="https://www.facebook.com/sharer.php?u=https://www.mdpi.com/2985378" title="facebook" target="_blank" rel="noopener noreferrer"> <i class="fa fa-facebook-square" style="font-size: 30px;"></i> </a> <a href="javascript:void(0);" title="Wechat" data-reveal-id="weixin-share-modal"> <i class="fa fa-weixin-square" style="font-size: 26px;"></i> </a> <a href="http://www.reddit.com/submit?url=https://www.mdpi.com/2985378" title="Reddit" target="_blank" rel="noopener noreferrer"> <i class="fa fa-reddit-square" style="font-size: 30px;"></i> </a> <a href="http://www.mendeley.com/import/?url=https://www.mdpi.com/2985378" title="Mendeley" target="_blank" rel="noopener noreferrer"> <i class="fa fa-mendeley-square" style="font-size: 30px;"></i> </a> </div> <div class="in-tab" style="padding-top: 0px!important; margin-top: 15px;"> <div><b>MDPI and ACS Style</b></div> <p> Deidda, V.; Ventisette, I.; Langione, M.; Giammarino, L.; Pioner, J.M.; Credi, C.; Carpi, F. 3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes. <em>J. Funct. Biomater.</em> <b>2024</b>, <em>15</em>, 297. https://doi.org/10.3390/jfb15100297 </p> <div style="display: block"> <b>AMA Style</b><br> <p> Deidda V, Ventisette I, Langione M, Giammarino L, Pioner JM, Credi C, Carpi F. 3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes. <em>Journal of Functional Biomaterials</em>. 2024; 15(10):297. https://doi.org/10.3390/jfb15100297 </p> <b>Chicago/Turabian Style</b><br> <p> Deidda, Virginia, Isabel Ventisette, Marianna Langione, Lucrezia Giammarino, Josè Manuel Pioner, Caterina Credi, and Federico Carpi. 2024. "3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes" <em>Journal of Functional Biomaterials</em> 15, no. 10: 297. https://doi.org/10.3390/jfb15100297 </p> <b>APA Style</b><br> <p> Deidda, V., Ventisette, I., Langione, M., Giammarino, L., Pioner, J. M., Credi, C., & Carpi, F. (2024). 3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes. <em>Journal of Functional Biomaterials</em>, <em>15</em>(10), 297. https://doi.org/10.3390/jfb15100297 </p> </div> </div> <div class="info-box no-margin"> Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details <a target="_blank" href="https://www.mdpi.com/about/announcements/784">here</a>. </div> <h2><a name="metrics"></a>Article Metrics</h2> <div class="row"> <div class="small-12 columns"> <div id="loaded_cite_count" style="display:none">No</div> <div id="framed_div_cited_count" class="in-tab" style="display: none; overflow: auto;"></div> <div id="loaded" style="display:none">No</div> <div id="framed_div" class="in-tab" style="display: none; margin-top: 10px;"></div> </div> <div class="small-12 columns"> <div id="article_stats_div" style="display: none; margin-bottom: 1em;"> <h3>Article Access Statistics</h3> <div id="article_stats_swf" ></div> For more information on the journal statistics, click <a href="/journal/jfb/stats">here</a>. <div class="info-box"> Multiple requests from the same IP address are counted as one view. </div> </div> </div> </div> </div> </div> </article> </div> <div id="supplementaryModal" class="reveal-modal reveal-modal-new" data-reveal aria-labelledby="Captcha" aria-hidden="true" role="dialog"> <div class="row"> <div class="large-12 medium-12 small-12 columns"> <h2>Supplementary Material</h2> <div class="custom-accordion-for-small-screen-content show-for-medium-up"> <div class="in-tab"> <ul style="margin:0; list-style: none; overflow: auto;"> <li><a name="supplementary_file1"></a><b>Supplementary File 1:</b> <p> <a href="/2079-4983/15/10/297/s1?version=1728115487"> ZIP-Document </a> (ZIP, 48502 KiB) </p> </li> </ul> </div> </div> </div> </div> <a class="close-reveal-modal" aria-label="Close"> <i class="material-icons">clear</i> </a> </div> </div></div> <div class="webpymol-controls webpymol-controls-template" style="margin-top: 10px; display: none;"> <a class="bzoom">Zoom</a> <span style="display: inline-block; margin-left: 5px; margin-right: 5px;">|</span> <a class="borient"> Orient </a> <span style="display: inline-block; margin-left: 5px; margin-right: 5px;">|</span> <a class="blines"> As Lines </a> <span style="display: inline-block; margin-left: 5px; margin-right: 5px;">|</span> <a class="bsticks"> As Sticks </a> <span style="display: inline-block; margin-left: 5px; margin-right: 5px;">|</span> <a class="bcartoon"> As Cartoon </a> <span style="display: inline-block; margin-left: 5px; margin-right: 5px;">|</span> <a class="bsurface"> As Surface </a> <span style="display: inline-block; margin-left: 5px; margin-right: 5px;">|</span> <a class="bprevscene">Previous Scene</a> <span style="display: inline-block; margin-left: 5px; margin-right: 5px;">|</span> <a class="bnextscene">Next Scene</a> </div> <div id="scifeed-modal" class="reveal-modal reveal-modal-new" data-reveal aria-labelledby="modalTitle" aria-hidden="true" role="dialog"> </div> <div id="recommended-articles-modal" class="reveal-modal reveal-modal-new" data-reveal aria-labelledby="modalTitle" aria-hidden="true" role="dialog"> </div> <div id="author-biographies-modal" class="reveal-modal reveal-modal-new" data-reveal aria-labelledby="modalTitle" aria-hidden="true" role="dialog"> </div> <div id="cite-modal" class="reveal-modal reveal-modal-new" data-reveal aria-labelledby="Captcha" aria-hidden="true" role="dialog"> <div class="row"> <div class="small-12 columns"> <h2 style="margin: 0;">Cite</h2> </div> <div class="small-12 columns">  <form style="margin:0; padding:0; display:inline;" name="export-bibtex" method="POST" action="/export"> <input type="hidden" name="articles_ids[]" value="1492689"> <input type="hidden" name="export_format_top" value="bibtex"> <input type="hidden" name="export_submit_top" value=""> </form>  <form style="margin:0; padding:0; display:inline;" name="export-endnote" method="POST" action="/export"> <input type="hidden" name="articles_ids[]" value="1492689"> <input type="hidden" name="export_format_top" value="endnote_no_abstract"> <input type="hidden" name="export_submit_top" value=""> </form>  <form style="margin:0; padding:0; display:inline;" name="export-ris" method="POST" action="/export"> <input type="hidden" name="articles_ids[]" value="1492689"> <input type="hidden" name="export_format_top" value="ris"> <input type="hidden" name="export_submit_top" value=""> </form> <div> Export citation file: <a href="javascript:window.document.forms['export-bibtex'].submit()">BibTeX</a> | <a href="javascript:window.document.forms['export-endnote'].submit()">EndNote</a> | <a href="javascript:window.document.forms['export-ris'].submit()">RIS</a> </div> </div> <div class="small-12 columns"> <div class="in-tab"> <div><b>MDPI and ACS Style</b></div> <p> Deidda, V.; Ventisette, I.; Langione, M.; Giammarino, L.; Pioner, J.M.; Credi, C.; Carpi, F. 3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes. <em>J. Funct. Biomater.</em> <b>2024</b>, <em>15</em>, 297. https://doi.org/10.3390/jfb15100297 </p> <div style="display: block"> <b>AMA Style</b><br> <p> Deidda V, Ventisette I, Langione M, Giammarino L, Pioner JM, Credi C, Carpi F. 3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes. <em>Journal of Functional Biomaterials</em>. 2024; 15(10):297. https://doi.org/10.3390/jfb15100297 </p> <b>Chicago/Turabian Style</b><br> <p> Deidda, Virginia, Isabel Ventisette, Marianna Langione, Lucrezia Giammarino, Josè Manuel Pioner, Caterina Credi, and Federico Carpi. 2024. "3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes" <em>Journal of Functional Biomaterials</em> 15, no. 10: 297. https://doi.org/10.3390/jfb15100297 </p> <b>APA Style</b><br> <p> Deidda, V., Ventisette, I., Langione, M., Giammarino, L., Pioner, J. M., Credi, C., & Carpi, F. (2024). 3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes. <em>Journal of Functional Biomaterials</em>, <em>15</em>(10), 297. https://doi.org/10.3390/jfb15100297 </p> </div> </div> <div class="info-box no-margin"> Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details <a target="_blank" href="https://www.mdpi.com/about/announcements/784">here</a>. </div> </div> </div> <a class="close-reveal-modal" aria-label="Close"> <i class="material-icons">clear</i> </a> </div> </div> </div> </div> </div> </section> <div id="footer"> <div class="journal-info"> <span> <em><a class="Var_JournalInfo" href="/journal/jfb">J. Funct. Biomater.</a></em>, EISSN 2079-4983, Published by MDPI </span> <div class="large-right"> <span> <a href="/rss/journal/jfb" class="rss-link">RSS</a> </span> <span> <a href="/journal/jfb/toc-alert">Content Alert</a> </span> </div> </div> <div class="row full-width footer-links" data-equalizer="footer" data-equalizer-mq="small"> <div class="large-2 large-push-4 medium-3 small-6 columns" data-equalizer-watch="footer"> <h3> Further Information </h3> <a href="/apc"> Article Processing Charges </a> <a href="/about/payment"> Pay an Invoice </a> <a href="/openaccess"> Open Access Policy </a> <a href="/about/contact"> Contact MDPI </a> <a href="https://careers.mdpi.com" target="_blank" rel="noopener noreferrer"> Jobs at MDPI </a> </div> <div class="large-2 large-push-4 medium-3 small-6 columns" data-equalizer-watch="footer"> <h3> Guidelines </h3> <a href="/authors"> For Authors </a> <a href="/reviewers"> For Reviewers </a> <a href="/editors"> For Editors </a> <a href="/librarians"> For Librarians </a> <a href="/publishing_services"> For Publishers </a> <a href="/societies"> For Societies </a> <a href="/conference_organizers"> For Conference Organizers </a> </div> <div class="large-2 large-push-4 medium-3 small-6 columns"> <h3> MDPI Initiatives </h3> <a href="https://sciforum.net" target="_blank" rel="noopener noreferrer"> Sciforum </a> <a href="https://www.mdpi.com/books" target="_blank" rel="noopener noreferrer"> MDPI Books </a> <a href="https://www.preprints.org" target="_blank" rel="noopener noreferrer"> Preprints.org </a> <a href="https://www.scilit.com" target="_blank" rel="noopener noreferrer"> Scilit </a> <a href="https://sciprofiles.com?utm_source=mpdi.com&utm_medium=bottom_menu&utm_campaign=initiative" target="_blank" rel="noopener noreferrer"> SciProfiles </a> <a href="https://encyclopedia.pub" target="_blank" rel="noopener noreferrer"> Encyclopedia </a> <a href="https://jams.pub" target="_blank" rel="noopener noreferrer"> JAMS </a> <a href="/about/proceedings"> Proceedings Series </a> </div> <div class="large-2 large-push-4 medium-3 small-6 right-border-large-without columns UA_FooterFollowMDPI"> <h3> Follow MDPI </h3> <a href="https://www.linkedin.com/company/mdpi" target="_blank" rel="noopener noreferrer"> LinkedIn </a> <a href="https://www.facebook.com/MDPIOpenAccessPublishing" target="_blank" rel="noopener noreferrer"> Facebook </a> <a href="https://twitter.com/MDPIOpenAccess" target="_blank" rel="noopener noreferrer"> Twitter </a> </div> <div id="footer-subscribe" class="large-4 large-pull-8 medium-12 small-12 left-border-large columns"> <div class="footer-subscribe__container"> <img class="show-for-large-up" src="https://pub.mdpi-res.com/img/design/mdpi-pub-logo-white-small.png?71d18e5f805839ab?1739771134" alt="MDPI" title="MDPI Open Access Journals" style="height: 50px; margin-bottom: 10px;"> <form id="newsletter" method="POST" action="/subscribe"> <p> Subscribe to receive issue release notifications and newsletters from MDPI journals </p> <select multiple id="newsletter-journal" class="foundation-select" name="journals[]"> <option value="acoustics">Acoustics</option> <option value="amh">Acta Microbiologica Hellenica</option> <option value="actuators">Actuators</option> <option value="adhesives">Adhesives</option> <option value="admsci">Administrative Sciences</option> <option value="adolescents">Adolescents</option> <option value="arm">Advances in Respiratory Medicine</option> <option value="aerobiology">Aerobiology</option> <option value="aerospace">Aerospace</option> <option value="agriculture">Agriculture</option> <option value="agriengineering">AgriEngineering</option> <option value="agrochemicals">Agrochemicals</option> <option value="agronomy">Agronomy</option> <option value="ai">AI</option> <option value="aisens">AI Sensors</option> <option value="air">Air</option> <option value="algorithms">Algorithms</option> <option value="allergies">Allergies</option> <option value="alloys">Alloys</option> <option value="analytica">Analytica</option> <option value="analytics">Analytics</option> <option value="anatomia">Anatomia</option> <option value="anesthres">Anesthesia Research</option> <option value="animals">Animals</option> <option value="antibiotics">Antibiotics</option> <option value="antibodies">Antibodies</option> <option value="antioxidants">Antioxidants</option> <option value="applbiosci">Applied Biosciences</option> <option value="applmech">Applied Mechanics</option> <option value="applmicrobiol">Applied Microbiology</option> <option value="applnano">Applied Nano</option> <option value="applsci">Applied Sciences</option> <option value="asi">Applied System Innovation</option> <option value="appliedchem">AppliedChem</option> <option value="appliedmath">AppliedMath</option> <option value="aquacj">Aquaculture Journal</option> <option value="architecture">Architecture</option> <option value="arthropoda">Arthropoda</option> <option value="arts">Arts</option> <option value="astronomy">Astronomy</option> <option value="atmosphere">Atmosphere</option> <option value="atoms">Atoms</option> <option value="audiolres">Audiology Research</option> <option value="automation">Automation</option> <option value="axioms">Axioms</option> <option value="bacteria">Bacteria</option> <option value="batteries">Batteries</option> <option value="behavsci">Behavioral Sciences</option> <option value="beverages">Beverages</option> <option value="BDCC">Big Data and Cognitive Computing</option> <option value="biochem">BioChem</option> <option value="bioengineering">Bioengineering</option> <option value="biologics">Biologics</option> <option value="biology">Biology</option> <option value="blsf">Biology and Life Sciences Forum</option> <option value="biomass">Biomass</option> <option value="biomechanics">Biomechanics</option> <option value="biomed">BioMed</option> <option value="biomedicines">Biomedicines</option> <option value="biomedinformatics">BioMedInformatics</option> <option value="biomimetics">Biomimetics</option> <option value="biomolecules">Biomolecules</option> <option value="biophysica">Biophysica</option> <option value="biosensors">Biosensors</option> <option value="biosphere">Biosphere</option> <option value="biotech">BioTech</option> <option value="birds">Birds</option> <option value="blockchains">Blockchains</option> <option value="brainsci">Brain Sciences</option> <option value="buildings">Buildings</option> <option value="businesses">Businesses</option> <option value="carbon">C</option> <option value="cancers">Cancers</option> <option value="cardiogenetics">Cardiogenetics</option> <option value="catalysts">Catalysts</option> <option value="cells">Cells</option> <option value="ceramics">Ceramics</option> <option value="challenges">Challenges</option> <option value="ChemEngineering">ChemEngineering</option> <option value="chemistry">Chemistry</option> <option value="chemproc">Chemistry Proceedings</option> <option value="chemosensors">Chemosensors</option> <option value="children">Children</option> <option value="chips">Chips</option> <option value="civileng">CivilEng</option> <option value="cleantechnol">Clean Technologies</option> <option value="climate">Climate</option> <option value="ctn">Clinical and Translational Neuroscience</option> <option value="clinbioenerg">Clinical Bioenergetics</option> <option value="clinpract">Clinics and Practice</option> <option value="clockssleep">Clocks & Sleep</option> <option value="coasts">Coasts</option> <option value="coatings">Coatings</option> <option value="colloids">Colloids and Interfaces</option> <option value="colorants">Colorants</option> <option value="commodities">Commodities</option> <option value="complications">Complications</option> <option value="compounds">Compounds</option> <option value="computation">Computation</option> <option value="csmf">Computer Sciences & Mathematics Forum</option> <option value="computers">Computers</option> <option value="condensedmatter">Condensed Matter</option> <option value="conservation">Conservation</option> <option value="constrmater">Construction Materials</option> <option value="cmd">Corrosion and Materials Degradation</option> <option value="cosmetics">Cosmetics</option> <option value="covid">COVID</option> <option value="cmtr">Craniomaxillofacial Trauma & Reconstruction</option> <option value="crops">Crops</option> <option value="cryo">Cryo</option> <option value="cryptography">Cryptography</option> <option value="crystals">Crystals</option> <option value="cimb">Current Issues in Molecular Biology</option> <option value="curroncol">Current Oncology</option> <option value="dairy">Dairy</option> <option value="data">Data</option> <option value="dentistry">Dentistry Journal</option> <option value="dermato">Dermato</option> <option value="dermatopathology">Dermatopathology</option> <option value="designs">Designs</option> <option value="diabetology">Diabetology</option> <option value="diagnostics">Diagnostics</option> <option value="dietetics">Dietetics</option> <option value="digital">Digital</option> <option value="disabilities">Disabilities</option> <option value="diseases">Diseases</option> <option value="diversity">Diversity</option> <option value="dna">DNA</option> <option value="drones">Drones</option> <option value="ddc">Drugs and Drug Candidates</option> <option value="dynamics">Dynamics</option> <option value="earth">Earth</option> <option value="ecologies">Ecologies</option> <option value="econometrics">Econometrics</option> <option value="economies">Economies</option> <option value="education">Education Sciences</option> <option value="electricity">Electricity</option> <option value="electrochem">Electrochem</option> <option value="electronicmat">Electronic Materials</option> <option value="electronics">Electronics</option> <option value="ecm">Emergency Care and Medicine</option> <option value="encyclopedia">Encyclopedia</option> <option value="endocrines">Endocrines</option> <option value="energies">Energies</option> <option value="esa">Energy Storage and Applications</option> <option value="eng">Eng</option> <option value="engproc">Engineering Proceedings</option> <option value="entropy">Entropy</option> <option value="eesp">Environmental and Earth Sciences Proceedings</option> <option value="environments">Environments</option> <option value="epidemiologia">Epidemiologia</option> <option value="epigenomes">Epigenomes</option> <option value="ebj">European Burn Journal</option> <option value="ejihpe">European Journal of Investigation in Health, Psychology and Education</option> <option value="fermentation">Fermentation</option> <option value="fibers">Fibers</option> <option value="fintech">FinTech</option> <option value="fire">Fire</option> <option value="fishes">Fishes</option> <option value="fluids">Fluids</option> <option value="foods">Foods</option> <option value="forecasting">Forecasting</option> <option value="forensicsci">Forensic Sciences</option> <option value="forests">Forests</option> <option value="fossstud">Fossil Studies</option> <option value="foundations">Foundations</option> <option value="fractalfract">Fractal and Fractional</option> <option value="fuels">Fuels</option> <option value="future">Future</option> <option value="futureinternet">Future Internet</option> <option value="futurepharmacol">Future Pharmacology</option> <option value="futuretransp">Future Transportation</option> <option value="galaxies">Galaxies</option> <option value="games">Games</option> <option value="gases">Gases</option> <option value="gastroent">Gastroenterology Insights</option> <option value="gastrointestdisord">Gastrointestinal Disorders</option> <option value="gastronomy">Gastronomy</option> <option value="gels">Gels</option> <option value="genealogy">Genealogy</option> <option value="genes">Genes</option> <option value="geographies">Geographies</option> <option value="geohazards">GeoHazards</option> <option value="geomatics">Geomatics</option> <option value="geometry">Geometry</option> <option value="geosciences">Geosciences</option> <option value="geotechnics">Geotechnics</option> <option value="geriatrics">Geriatrics</option> <option value="glacies">Glacies</option> <option value="gucdd">Gout, Urate, and Crystal Deposition Disease</option> <option value="grasses">Grasses</option> <option value="greenhealth">Green Health</option> <option value="hardware">Hardware</option> <option value="healthcare">Healthcare</option> <option value="hearts">Hearts</option> <option value="hemato">Hemato</option> <option value="hematolrep">Hematology Reports</option> <option value="heritage">Heritage</option> <option value="histories">Histories</option> <option value="horticulturae">Horticulturae</option> <option value="hospitals">Hospitals</option> <option value="humanities">Humanities</option> <option value="humans">Humans</option> <option value="hydrobiology">Hydrobiology</option> <option value="hydrogen">Hydrogen</option> <option value="hydrology">Hydrology</option> <option value="hygiene">Hygiene</option> <option value="immuno">Immuno</option> <option value="idr">Infectious Disease Reports</option> <option value="informatics">Informatics</option> <option value="information">Information</option> <option value="infrastructures">Infrastructures</option> <option value="inorganics">Inorganics</option> <option value="insects">Insects</option> <option value="instruments">Instruments</option> <option value="iic">Intelligent Infrastructure and Construction</option> <option value="ijerph">International Journal of Environmental Research and Public Health</option> <option value="ijfs">International Journal of Financial Studies</option> <option value="ijms">International Journal of Molecular Sciences</option> <option value="IJNS">International Journal of Neonatal Screening</option> <option value="ijom">International Journal of Orofacial Myology and Myofunctional Therapy</option> <option value="ijpb">International Journal of Plant Biology</option> <option value="ijt">International Journal of Topology</option> <option value="ijtm">International Journal of Translational Medicine</option> <option value="ijtpp">International Journal of Turbomachinery, Propulsion and Power</option> <option value="ime">International Medical Education</option> <option value="inventions">Inventions</option> <option value="IoT">IoT</option> <option value="ijgi">ISPRS International Journal of Geo-Information</option> <option value="J">J</option> <option value="jal">Journal of Ageing and Longevity</option> <option value="jcdd">Journal of Cardiovascular Development and Disease</option> <option value="jcto">Journal of Clinical & Translational Ophthalmology</option> <option value="jcm">Journal of Clinical Medicine</option> <option value="jcs">Journal of Composites Science</option> <option value="jcp">Journal of Cybersecurity and Privacy</option> <option value="jdad">Journal of Dementia and Alzheimer's Disease</option> <option value="jdb">Journal of Developmental Biology</option> <option value="jeta">Journal of Experimental and Theoretical Analyses</option> <option value="jemr">Journal of Eye Movement Research</option> <option value="jfb">Journal of Functional Biomaterials</option> <option value="jfmk">Journal of Functional Morphology and Kinesiology</option> <option value="jof">Journal of Fungi</option> <option value="jimaging">Journal of Imaging</option> <option value="jintelligence">Journal of Intelligence</option> <option value="jlpea">Journal of Low Power Electronics and Applications</option> <option value="jmmp">Journal of Manufacturing and Materials Processing</option> <option value="jmse">Journal of Marine Science and Engineering</option> <option value="jmahp">Journal of Market Access & Health Policy</option> <option value="jmms">Journal of Mind and Medical Sciences</option> <option value="jmp">Journal of Molecular Pathology</option> <option value="jnt">Journal of Nanotheranostics</option> <option value="jne">Journal of Nuclear Engineering</option> <option value="ohbm">Journal of Otorhinolaryngology, Hearing and Balance Medicine</option> <option value="jop">Journal of Parks</option> <option value="jpm">Journal of Personalized Medicine</option> <option value="jpbi">Journal of Pharmaceutical and BioTech Industry</option> <option value="jor">Journal of Respiration</option> <option value="jrfm">Journal of Risk and Financial Management</option> <option value="jsan">Journal of Sensor and Actuator Networks</option> <option value="joma">Journal of the Oman Medical Association</option> <option value="jtaer">Journal of Theoretical and Applied Electronic Commerce Research</option> <option value="jvd">Journal of Vascular Diseases</option> <option value="jox">Journal of Xenobiotics</option> <option value="jzbg">Journal of Zoological and Botanical Gardens</option> <option value="journalmedia">Journalism and Media</option> <option value="kidneydial">Kidney and Dialysis</option> <option value="kinasesphosphatases">Kinases and Phosphatases</option> <option value="knowledge">Knowledge</option> <option value="labmed">LabMed</option> <option value="laboratories">Laboratories</option> <option value="land">Land</option> <option value="languages">Languages</option> <option value="laws">Laws</option> <option value="life">Life</option> <option value="limnolrev">Limnological Review</option> <option value="lipidology">Lipidology</option> <option value="liquids">Liquids</option> <option value="literature">Literature</option> <option value="livers">Livers</option> <option value="logics">Logics</option> <option value="logistics">Logistics</option> <option value="lubricants">Lubricants</option> <option value="lymphatics">Lymphatics</option> <option value="make">Machine Learning and Knowledge Extraction</option> <option value="machines">Machines</option> <option value="macromol">Macromol</option> <option value="magnetism">Magnetism</option> <option value="magnetochemistry">Magnetochemistry</option> <option value="marinedrugs">Marine Drugs</option> <option value="materials">Materials</option> <option value="materproc">Materials Proceedings</option> <option value="mca">Mathematical and Computational Applications</option> <option value="mathematics">Mathematics</option> <option value="medsci">Medical Sciences</option> <option value="msf">Medical Sciences Forum</option> <option value="medicina">Medicina</option> <option value="medicines">Medicines</option> <option value="membranes">Membranes</option> <option value="merits">Merits</option> <option value="metabolites">Metabolites</option> <option value="metals">Metals</option> <option value="meteorology">Meteorology</option> <option value="methane">Methane</option> <option value="mps">Methods and Protocols</option> <option value="metrics">Metrics</option> <option value="metrology">Metrology</option> <option value="micro">Micro</option> <option value="microbiolres">Microbiology Research</option> <option value="micromachines">Micromachines</option> <option value="microorganisms">Microorganisms</option> <option value="microplastics">Microplastics</option> <option value="microwave">Microwave</option> <option value="minerals">Minerals</option> <option value="mining">Mining</option> <option value="modelling">Modelling</option> <option value="mmphys">Modern Mathematical Physics</option> <option value="molbank">Molbank</option> <option value="molecules">Molecules</option> <option value="mti">Multimodal Technologies and Interaction</option> <option value="muscles">Muscles</option> <option value="nanoenergyadv">Nanoenergy Advances</option> <option value="nanomanufacturing">Nanomanufacturing</option> <option value="nanomaterials">Nanomaterials</option> <option value="ndt">NDT</option> <option value="network">Network</option> <option value="neuroglia">Neuroglia</option> <option value="neurolint">Neurology International</option> <option value="neurosci">NeuroSci</option> <option value="nitrogen">Nitrogen</option> <option value="ncrna">Non-Coding RNA</option> <option value="nursrep">Nursing Reports</option> <option value="nutraceuticals">Nutraceuticals</option> <option value="nutrients">Nutrients</option> <option value="obesities">Obesities</option> <option value="oceans">Oceans</option> <option value="onco">Onco</option> <option value="optics">Optics</option> <option value="oral">Oral</option> <option value="organics">Organics</option> <option value="organoids">Organoids</option> <option value="osteology">Osteology</option> <option value="oxygen">Oxygen</option> <option value="parasitologia">Parasitologia</option> <option value="particles">Particles</option> <option value="pathogens">Pathogens</option> <option value="pathophysiology">Pathophysiology</option> <option value="pediatrrep">Pediatric Reports</option> <option value="pets">Pets</option> <option value="pharmaceuticals">Pharmaceuticals</option> <option value="pharmaceutics">Pharmaceutics</option> <option value="pharmacoepidemiology">Pharmacoepidemiology</option> <option value="pharmacy">Pharmacy</option> <option value="philosophies">Philosophies</option> <option value="photochem">Photochem</option> <option value="photonics">Photonics</option> <option value="phycology">Phycology</option> <option value="physchem">Physchem</option> <option value="psf">Physical Sciences Forum</option> <option value="physics">Physics</option> <option value="physiologia">Physiologia</option> <option value="plants">Plants</option> <option value="plasma">Plasma</option> <option value="platforms">Platforms</option> <option value="pollutants">Pollutants</option> <option value="polymers">Polymers</option> <option value="polysaccharides">Polysaccharides</option> <option value="populations">Populations</option> <option value="poultry">Poultry</option> <option value="powders">Powders</option> <option value="proceedings">Proceedings</option> <option value="processes">Processes</option> <option value="prosthesis">Prosthesis</option> <option value="proteomes">Proteomes</option> <option value="psychiatryint">Psychiatry International</option> <option value="psychoactives">Psychoactives</option> <option value="psycholint">Psychology International</option> <option value="publications">Publications</option> <option value="qubs">Quantum Beam Science</option> <option value="quantumrep">Quantum Reports</option> <option value="quaternary">Quaternary</option> <option value="radiation">Radiation</option> <option value="reactions">Reactions</option> <option value="realestate">Real Estate</option> <option value="receptors">Receptors</option> <option value="recycling">Recycling</option> <option value="rsee">Regional Science and Environmental Economics</option> <option value="religions">Religions</option> <option value="remotesensing">Remote Sensing</option> <option value="reports">Reports</option> <option value="reprodmed">Reproductive Medicine</option> <option value="resources">Resources</option> <option value="rheumato">Rheumato</option> <option value="risks">Risks</option> <option value="robotics">Robotics</option> <option value="ruminants">Ruminants</option> <option value="safety">Safety</option> <option value="sci">Sci</option> <option value="scipharm">Scientia Pharmaceutica</option> <option value="sclerosis">Sclerosis</option> <option value="seeds">Seeds</option> <option value="sensors">Sensors</option> <option value="separations">Separations</option> <option value="sexes">Sexes</option> <option value="signals">Signals</option> <option value="sinusitis">Sinusitis</option> <option value="smartcities">Smart Cities</option> <option value="socsci">Social Sciences</option> <option value="siuj">Société Internationale d’Urologie Journal</option> <option value="societies">Societies</option> <option value="software">Software</option> <option value="soilsystems">Soil Systems</option> <option value="solar">Solar</option> <option value="solids">Solids</option> <option value="spectroscj">Spectroscopy Journal</option> <option value="sports">Sports</option> <option value="standards">Standards</option> <option value="stats">Stats</option> <option value="stresses">Stresses</option> <option value="surfaces">Surfaces</option> <option value="surgeries">Surgeries</option> <option value="std">Surgical Techniques Development</option> <option value="sustainability">Sustainability</option> <option value="suschem">Sustainable Chemistry</option> <option value="symmetry">Symmetry</option> <option value="synbio">SynBio</option> <option value="systems">Systems</option> <option value="targets">Targets</option> <option value="taxonomy">Taxonomy</option> <option value="technologies">Technologies</option> <option value="telecom">Telecom</option> <option value="textiles">Textiles</option> <option value="thalassrep">Thalassemia Reports</option> <option value="therapeutics">Therapeutics</option> <option value="thermo">Thermo</option> <option value="timespace">Time and Space</option> <option value="tomography">Tomography</option> <option value="tourismhosp">Tourism and Hospitality</option> <option value="toxics">Toxics</option> <option value="toxins">Toxins</option> <option value="transplantology">Transplantology</option> <option value="traumacare">Trauma Care</option> <option value="higheredu">Trends in Higher Education</option> <option value="tropicalmed">Tropical Medicine and Infectious Disease</option> <option value="universe">Universe</option> <option value="urbansci">Urban Science</option> <option value="uro">Uro</option> <option value="vaccines">Vaccines</option> <option value="vehicles">Vehicles</option> <option value="venereology">Venereology</option> <option value="vetsci">Veterinary Sciences</option> <option value="vibration">Vibration</option> <option value="virtualworlds">Virtual Worlds</option> <option value="viruses">Viruses</option> <option value="vision">Vision</option> <option value="waste">Waste</option> <option value="water">Water</option> <option value="wild">Wild</option> <option value="wind">Wind</option> <option value="women">Women</option> <option value="world">World</option> <option value="wevj">World Electric Vehicle Journal</option> <option value="youth">Youth</option> <option value="zoonoticdis">Zoonotic Diseases</option> </select> <input name="email" type="email" placeholder="Enter your email address..." required="required" /> <button class="genericCaptcha button button--dark UA_FooterNewsletterSubscribeButton" type="submit">Subscribe</button> </form> </div> </div> </div> <div id="footer-copyright"> <div class="row"> <div class="columns large-6 medium-6 small-12 text-left"> © 1996-2025 MDPI (Basel, Switzerland) unless otherwise stated </div> <div class="columns large-6 medium-6 small-12 small-text-left medium-text-right large-text-right"> <a data-dropdown="drop-view-disclaimer" aria-controls="drop-view-disclaimer" aria-expanded="false" data-options="align:top; is_hover:true; hover_timeout:2000;"> Disclaimer </a> <div id="drop-view-disclaimer" class="f-dropdown label__btn__dropdown label__btn__dropdown--wide text-left" data-dropdown-content aria-hidden="true" tabindex="-1"> Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. </div> <a href="/about/terms-and-conditions"> Terms and Conditions </a> <a href="/about/privacy"> Privacy Policy </a> </div> </div> </div> </div> <div id="cookie-notification" class="js-allow-cookies" style="display: none;"> <div class="columns large-10 medium-10 small-12"> We use cookies on our website to ensure you get the best experience.<br class="show-for-medium-up"/> Read more about our cookies <a href="/about/privacy">here</a>. </div> <div class="columns large-2 medium-2 small-12 small-only-text-left text-right"> <a class="button button--default" href="/accept_cookies">Accept</a> </div> </div> </div> <div id="main-share-modal" class="reveal-modal reveal-modal-new reveal-modal-new--small" data-reveal aria-labelledby="modalTitle" aria-hidden="true" role="dialog"> <div class="row"> <div class="small-12 columns"> <h2 style="margin: 0;">Share Link</h2> </div> <div class="small-12 columns"> <div class="social-media-links UA_ShareModalLinks" style="text-align: left;"> <a href="/cdn-cgi/l/email-protection#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" title="Email"> <i class="fa fa-envelope-square" style="font-size: 30px;"></i> </a> <a href="https://twitter.com/intent/tweet?text=3D-Printable+Gelatin+Methacrylate-Xanthan+Gum+Hydrogel+Bioink+Enabling+Human+Induced+Pluripotent+Stem+Cell+Differentiation+into+Cardiomyocytes&hashtags=mdpijfb&url=https%3A%2F%2Fwww.mdpi.com%2F2985378&via=JFB_MDPI" onclick="windowOpen(this.href,600,800); return false" title="Twitter" target="_blank" rel="noopener noreferrer"> <i class="fa fa-twitter-x-square" style="font-size: 30px;"></i> </a> <a href=" http://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fwww.mdpi.com%2F2985378&title=3D-Printable%20Gelatin%20Methacrylate-Xanthan%20Gum%20Hydrogel%20Bioink%20Enabling%20Human%20Induced%20Pluripotent%20Stem%20Cell%20Differentiation%20into%20Cardiomyocytes%26source%3Dhttps%3A%2F%2Fwww.mdpi.com%26summary%3DWe%20describe%20the%20development%20of%20a%20bioink%20to%20bioprint%20human%20induced%20pluripotent%20stem%20cells%20%28hiPSCs%29%20for%20possible%20cardiac%20tissue%20engineering%20using%20a%20gelatin%20methacrylate%20%28GelMA%29-based%20hydrogel.%20While%20previous%20studies%20have%20shown%20that%20GelMA%20at%20a%20low%20%5B...%5D" onclick="windowOpen(this.href,600,800); return false" title="LinkedIn" target="_blank" rel="noopener noreferrer"> <i class="fa fa-linkedin-square" style="font-size: 30px;"></i> </a> <a href="https://www.facebook.com/sharer.php?u=https://www.mdpi.com/2985378" title="facebook" target="_blank" rel="noopener noreferrer"> <i class="fa fa-facebook-square" style="font-size: 30px;"></i> </a> <a href="javascript:void(0);" title="Wechat" data-reveal-id="weixin-share-modal"> <i class="fa fa-weixin-square" style="font-size: 26px;"></i> </a> <a href="http://www.reddit.com/submit?url=https://www.mdpi.com/2985378" title="Reddit" target="_blank" rel="noopener noreferrer"> <i class="fa fa-reddit-square" style="font-size: 30px;"></i> </a> <a href="http://www.mendeley.com/import/?url=https://www.mdpi.com/2985378" title="Mendeley" target="_blank" rel="noopener noreferrer"> <i class="fa fa-mendeley-square" style="font-size: 30px;"></i> </a> <a href="http://www.citeulike.org/posturl?url=https://www.mdpi.com/2985378" title="CiteULike" target="_blank" rel="noopener noreferrer"> <i class="fa fa-citeulike-square" style="font-size: 30px;"></i> </a> </div> </div> <div class="small-9 columns"> <input id="js-clipboard-text" type="text" readonly value="https://www.mdpi.com/2985378" /> </div> <div class="small-3 columns text-left"> <a class="button button--color js-clipboard-copy" data-clipboard-target="#js-clipboard-text">Copy</a> </div> </div> <a class="close-reveal-modal" aria-label="Close"> <i class="material-icons">clear</i> </a> </div> <div id="weixin-share-modal" class="reveal-modal reveal-modal-new" data-reveal aria-labelledby="weixin-share-modal-title" aria-hidden="true" role="dialog"> <div class="row"> <div class="small-12 columns"> <h2 id="weixin-share-modal-title" style="margin: 0;">Share</h2> </div> <div class="small-12 columns"> <div class="weixin-qr-code-section"> <?xml version="1.0" standalone="no"?> <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"> <svg width="300" height="300" version="1.1" xmlns="http://www.w3.org/2000/svg"> <desc>https://www.mdpi.com/2985378</desc> <g id="elements" fill="black" stroke="none"> <rect x="0" y="0" width="12" height="12" /> <rect x="12" y="0" width="12" height="12" /> <rect x="24" y="0" width="12" height="12" /> <rect x="36" y="0" width="12" height="12" /> <rect x="48" y="0" width="12" height="12" /> <rect x="60" y="0" width="12" height="12" /> <rect x="72" y="0" width="12" height="12" /> <rect x="120" y="0" width="12" height="12" /> <rect x="168" y="0" width="12" height="12" /> <rect x="180" y="0" width="12" height="12" /> <rect x="216" y="0" width="12" height="12" /> <rect x="228" y="0" width="12" height="12" /> <rect x="240" y="0" width="12" height="12" /> <rect x="252" y="0" width="12" height="12" /> <rect x="264" y="0" width="12" height="12" /> <rect x="276" y="0" width="12" height="12" /> <rect x="288" y="0" width="12" height="12" /> <rect x="0" y="12" width="12" height="12" /> <rect x="72" y="12" width="12" height="12" /> <rect x="96" y="12" width="12" height="12" /> <rect x="108" y="12" width="12" height="12" /> <rect x="120" y="12" width="12" height="12" /> <rect x="156" y="12" width="12" height="12" /> <rect x="180" y="12" width="12" height="12" /> <rect x="192" y="12" width="12" height="12" /> <rect x="216" y="12" width="12" height="12" /> <rect x="288" y="12" width="12" height="12" /> <rect x="0" y="24" width="12" height="12" /> <rect x="24" y="24" width="12" height="12" /> <rect x="36" y="24" width="12" height="12" /> <rect x="48" y="24" width="12" height="12" /> <rect x="72" y="24" width="12" height="12" /> <rect x="96" y="24" width="12" height="12" /> <rect x="168" y="24" width="12" height="12" /> <rect x="180" y="24" width="12" height="12" /> <rect x="216" y="24" width="12" height="12" /> <rect x="240" y="24" width="12" height="12" /> <rect x="252" y="24" width="12" height="12" /> <rect x="264" y="24" width="12" height="12" /> <rect x="288" y="24" width="12" height="12" /> <rect x="0" y="36" width="12" height="12" /> <rect x="24" y="36" width="12" height="12" /> <rect x="36" y="36" width="12" height="12" /> <rect x="48" y="36" width="12" height="12" /> <rect x="72" y="36" width="12" height="12" /> <rect x="108" y="36" width="12" height="12" /> <rect x="168" y="36" width="12" height="12" /> <rect x="216" y="36" width="12" height="12" /> <rect x="240" y="36" width="12" height="12" /> <rect x="252" y="36" width="12" height="12" /> <rect x="264" y="36" width="12" height="12" /> <rect x="288" y="36" width="12" height="12" /> <rect x="0" y="48" width="12" height="12" /> <rect x="24" y="48" width="12" height="12" /> <rect x="36" y="48" width="12" height="12" /> <rect x="48" y="48" width="12" height="12" /> <rect x="72" y="48" width="12" height="12" /> <rect x="96" y="48" width="12" height="12" /> <rect x="108" y="48" width="12" height="12" /> <rect x="120" y="48" width="12" height="12" /> <rect x="144" y="48" width="12" height="12" /> <rect x="168" y="48" width="12" height="12" /> <rect x="180" y="48" width="12" height="12" /> <rect x="216" y="48" width="12" height="12" /> <rect x="240" y="48" width="12" height="12" /> <rect x="252" y="48" width="12" height="12" /> <rect x="264" y="48" width="12" height="12" /> <rect x="288" y="48" width="12" height="12" /> <rect x="0" y="60" width="12" height="12" /> <rect x="72" y="60" width="12" height="12" /> <rect x="96" y="60" width="12" height="12" /> <rect x="120" y="60" width="12" height="12" /> <rect x="180" y="60" width="12" height="12" /> <rect x="192" y="60" width="12" height="12" /> <rect x="216" y="60" width="12" height="12" /> <rect x="288" y="60" width="12" height="12" /> <rect x="0" y="72" width="12" height="12" /> <rect x="12" y="72" width="12" height="12" /> <rect x="24" y="72" width="12" height="12" /> <rect x="36" y="72" width="12" height="12" /> <rect x="48" y="72" width="12" height="12" /> <rect x="60" y="72" width="12" height="12" /> <rect x="72" y="72" width="12" height="12" /> <rect x="96" y="72" width="12" height="12" /> <rect x="120" y="72" width="12" height="12" /> <rect x="144" y="72" width="12" height="12" /> <rect x="168" y="72" width="12" height="12" /> <rect x="192" y="72" width="12" height="12" /> <rect x="216" y="72" width="12" height="12" /> <rect x="228" y="72" width="12" height="12" /> <rect x="240" y="72" width="12" height="12" /> <rect x="252" y="72" width="12" height="12" /> <rect x="264" y="72" width="12" height="12" /> <rect x="276" y="72" width="12" height="12" /> <rect x="288" y="72" width="12" height="12" /> <rect x="96" y="84" width="12" height="12" /> <rect x="120" y="84" width="12" height="12" /> <rect x="132" y="84" width="12" height="12" /> <rect x="168" y="84" width="12" height="12" /> <rect x="180" y="84" width="12" height="12" /> <rect x="192" y="84" width="12" height="12" /> <rect x="0" y="96" width="12" height="12" /> <rect x="12" y="96" width="12" height="12" /> <rect x="36" y="96" width="12" height="12" /> <rect x="72" y="96" width="12" height="12" /> <rect x="84" y="96" width="12" height="12" /> <rect x="132" y="96" width="12" height="12" /> <rect x="144" y="96" width="12" height="12" /> <rect x="156" y="96" width="12" height="12" /> <rect x="168" y="96" width="12" height="12" /> <rect x="180" y="96" width="12" height="12" /> <rect x="192" y="96" width="12" height="12" /> <rect x="216" y="96" width="12" height="12" /> <rect x="228" y="96" width="12" height="12" /> <rect x="240" y="96" width="12" height="12" /> <rect x="264" y="96" width="12" height="12" /> <rect x="276" y="96" width="12" height="12" /> <rect x="0" y="108" width="12" height="12" /> <rect x="24" y="108" width="12" height="12" /> <rect x="48" y="108" width="12" height="12" /> <rect x="84" y="108" width="12" height="12" /> <rect x="96" y="108" width="12" height="12" /> <rect x="108" y="108" width="12" height="12" /> <rect x="132" y="108" width="12" height="12" /> <rect x="192" y="108" width="12" height="12" /> <rect x="216" y="108" width="12" height="12" /> <rect x="288" y="108" width="12" height="12" /> <rect x="24" y="120" width="12" height="12" /> <rect x="36" y="120" width="12" height="12" /> <rect x="60" y="120" width="12" height="12" /> <rect x="72" y="120" width="12" height="12" /> <rect x="84" y="120" width="12" height="12" /> <rect x="132" y="120" width="12" height="12" /> <rect x="156" y="120" width="12" height="12" /> <rect x="204" y="120" width="12" height="12" /> <rect x="216" y="120" width="12" height="12" /> <rect x="276" y="120" width="12" height="12" /> <rect x="288" y="120" width="12" height="12" /> <rect x="0" y="132" width="12" height="12" /> <rect x="12" y="132" width="12" height="12" /> <rect x="24" y="132" width="12" height="12" /> <rect x="36" y="132" width="12" height="12" /> <rect x="108" y="132" width="12" height="12" /> <rect x="120" y="132" width="12" height="12" /> <rect x="156" y="132" width="12" height="12" /> <rect x="180" y="132" width="12" height="12" /> <rect x="204" y="132" width="12" height="12" /> <rect x="216" y="132" width="12" height="12" /> <rect x="240" y="132" width="12" height="12" /> <rect x="24" y="144" width="12" height="12" /> <rect x="72" y="144" width="12" height="12" /> <rect x="84" y="144" width="12" height="12" /> <rect x="120" y="144" width="12" height="12" /> <rect x="144" y="144" width="12" height="12" /> <rect x="156" y="144" width="12" height="12" /> <rect x="168" y="144" width="12" height="12" /> <rect x="204" y="144" width="12" height="12" /> <rect x="216" y="144" width="12" height="12" /> <rect x="228" y="144" width="12" height="12" /> <rect x="252" y="144" width="12" height="12" /> <rect x="276" y="144" width="12" height="12" /> <rect x="288" y="144" width="12" height="12" /> <rect x="24" y="156" width="12" height="12" /> <rect x="48" y="156" width="12" height="12" /> <rect x="84" y="156" width="12" height="12" /> <rect x="96" y="156" width="12" height="12" /> <rect x="216" y="156" width="12" height="12" /> <rect x="228" y="156" width="12" height="12" /> <rect x="252" y="156" width="12" height="12" /> <rect x="264" y="156" width="12" height="12" /> <rect x="288" y="156" width="12" height="12" /> <rect x="0" y="168" width="12" height="12" /> <rect x="24" y="168" width="12" height="12" /> <rect x="60" y="168" width="12" height="12" /> <rect x="72" y="168" width="12" height="12" /> <rect x="96" y="168" width="12" height="12" /> <rect x="108" y="168" width="12" height="12" /> <rect x="120" y="168" width="12" height="12" /> <rect x="144" y="168" width="12" height="12" /> <rect x="192" y="168" width="12" height="12" /> <rect x="216" y="168" width="12" height="12" /> <rect x="228" y="168" width="12" height="12" /> <rect x="240" y="168" width="12" height="12" /> <rect x="264" y="168" width="12" height="12" /> <rect x="288" y="168" width="12" height="12" /> <rect x="12" y="180" width="12" height="12" /> <rect x="24" y="180" width="12" height="12" /> <rect x="48" y="180" width="12" height="12" /> <rect x="120" y="180" width="12" height="12" /> <rect x="132" y="180" width="12" height="12" /> <rect x="156" y="180" width="12" height="12" /> <rect x="180" y="180" width="12" height="12" /> <rect x="192" y="180" width="12" height="12" /> <rect x="216" y="180" width="12" height="12" /> <rect x="240" y="180" width="12" height="12" /> <rect x="276" y="180" width="12" height="12" /> <rect x="0" y="192" width="12" height="12" /> <rect x="12" y="192" width="12" height="12" /> <rect x="24" y="192" width="12" height="12" /> <rect x="72" y="192" width="12" height="12" /> <rect x="84" y="192" width="12" height="12" /> <rect x="108" y="192" width="12" height="12" /> <rect x="120" y="192" width="12" height="12" /> <rect x="156" y="192" width="12" height="12" /> <rect x="192" y="192" width="12" height="12" /> <rect x="204" y="192" width="12" height="12" /> <rect x="216" y="192" width="12" height="12" /> <rect x="228" y="192" width="12" height="12" /> <rect x="240" y="192" width="12" height="12" /> <rect x="252" y="192" width="12" height="12" /> <rect x="264" y="192" width="12" height="12" /> <rect x="96" y="204" width="12" height="12" /> <rect x="120" y="204" width="12" height="12" /> <rect x="156" y="204" width="12" height="12" /> <rect x="168" y="204" width="12" height="12" /> <rect x="180" y="204" width="12" height="12" /> <rect x="192" y="204" width="12" height="12" /> <rect x="240" y="204" width="12" height="12" /> <rect x="252" y="204" width="12" height="12" /> <rect x="288" y="204" width="12" height="12" /> <rect x="0" y="216" width="12" height="12" /> <rect x="12" y="216" width="12" height="12" /> <rect x="24" y="216" width="12" height="12" /> <rect x="36" y="216" width="12" height="12" /> <rect x="48" y="216" width="12" height="12" /> <rect x="60" y="216" width="12" height="12" /> <rect x="72" y="216" width="12" height="12" /> <rect x="96" y="216" width="12" height="12" /> <rect x="108" y="216" width="12" height="12" /> <rect x="120" y="216" width="12" height="12" /> <rect x="132" y="216" width="12" height="12" /> <rect x="156" y="216" width="12" height="12" /> <rect x="180" y="216" width="12" height="12" /> <rect x="192" y="216" width="12" height="12" /> <rect x="216" y="216" width="12" height="12" /> <rect x="240" y="216" width="12" height="12" /> <rect x="252" y="216" width="12" height="12" /> <rect x="276" y="216" width="12" height="12" /> <rect x="288" y="216" width="12" height="12" /> <rect x="0" y="228" width="12" height="12" /> <rect x="72" y="228" width="12" height="12" /> <rect x="108" y="228" width="12" height="12" /> <rect x="120" y="228" width="12" height="12" /> <rect x="156" y="228" width="12" height="12" /> <rect x="168" y="228" width="12" height="12" /> <rect x="192" y="228" width="12" height="12" /> <rect x="240" y="228" width="12" height="12" /> <rect x="252" y="228" width="12" height="12" /> <rect x="264" y="228" width="12" height="12" /> <rect x="276" y="228" width="12" height="12" /> <rect x="0" y="240" width="12" height="12" /> <rect x="24" y="240" width="12" height="12" /> <rect x="36" y="240" width="12" height="12" /> <rect x="48" y="240" width="12" height="12" /> <rect x="72" y="240" width="12" height="12" /> <rect x="108" y="240" width="12" height="12" /> <rect x="120" y="240" width="12" height="12" /> <rect x="132" y="240" width="12" height="12" /> <rect x="144" y="240" width="12" height="12" /> <rect x="192" y="240" width="12" height="12" /> <rect x="204" y="240" width="12" height="12" /> <rect x="216" y="240" width="12" height="12" /> <rect x="228" y="240" width="12" height="12" /> <rect x="240" y="240" width="12" height="12" /> <rect x="252" y="240" width="12" height="12" /> <rect x="288" y="240" width="12" height="12" /> <rect x="0" y="252" width="12" height="12" /> <rect x="24" y="252" width="12" height="12" /> <rect x="36" y="252" width="12" height="12" /> <rect x="48" y="252" width="12" height="12" /> <rect x="72" y="252" width="12" height="12" /> <rect x="96" y="252" width="12" height="12" /> <rect x="120" y="252" width="12" height="12" /> <rect x="156" y="252" width="12" height="12" /> <rect x="168" y="252" width="12" height="12" /> <rect x="204" y="252" width="12" height="12" /> <rect x="228" y="252" width="12" height="12" /> <rect x="240" y="252" width="12" height="12" /> <rect x="252" y="252" width="12" height="12" /> <rect x="264" y="252" width="12" height="12" /> <rect x="0" y="264" width="12" height="12" /> <rect x="24" y="264" width="12" height="12" /> <rect x="36" y="264" width="12" height="12" /> <rect x="48" y="264" width="12" height="12" /> <rect x="72" y="264" width="12" height="12" /> <rect x="108" y="264" width="12" height="12" /> <rect x="132" y="264" width="12" height="12" /> <rect x="156" y="264" width="12" height="12" /> <rect x="168" y="264" width="12" height="12" /> <rect x="180" y="264" width="12" height="12" /> <rect x="192" y="264" width="12" height="12" /> <rect x="228" y="264" width="12" height="12" /> <rect x="240" y="264" width="12" height="12" /> <rect x="264" y="264" width="12" height="12" /> <rect x="288" y="264" width="12" height="12" /> <rect x="0" y="276" width="12" height="12" /> <rect x="72" y="276" width="12" height="12" /> <rect x="96" y="276" width="12" height="12" /> <rect x="120" y="276" width="12" height="12" /> <rect x="132" y="276" width="12" height="12" /> <rect x="156" y="276" width="12" height="12" /> <rect x="180" y="276" width="12" height="12" /> <rect x="192" y="276" width="12" height="12" /> <rect x="204" y="276" width="12" height="12" /> <rect x="216" y="276" width="12" height="12" /> <rect x="252" y="276" width="12" height="12" /> <rect x="0" y="288" width="12" height="12" /> <rect x="12" y="288" width="12" height="12" /> <rect x="24" y="288" width="12" height="12" /> <rect x="36" y="288" width="12" height="12" /> <rect x="48" y="288" width="12" height="12" /> <rect x="60" y="288" width="12" height="12" /> <rect x="72" y="288" width="12" height="12" /> <rect x="96" y="288" width="12" height="12" /> <rect x="108" y="288" width="12" height="12" /> <rect x="156" y="288" width="12" height="12" /> <rect x="168" y="288" width="12" height="12" /> <rect x="180" y="288" width="12" height="12" /> <rect x="192" y="288" width="12" height="12" /> <rect x="228" y="288" width="12" height="12" /> <rect x="276" y="288" width="12" height="12" /> <rect x="288" y="288" width="12" height="12" /> </g> </svg> </div> </div> </div> <a class="close-reveal-modal" aria-label="Close"> <i class="material-icons">clear</i> </a> </div> <a href="#" class="back-to-top"><span class="show-for-medium-up">Back to Top</span><span class="show-for-small">Top</span></a> <script data-cfasync="false" src="/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js"></script><script src="https://pub.mdpi-res.com/assets/js/modernizr-2.8.3.min.js?5227e0738f7f421d?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/jquery-1.12.4.min.js?4f252523d4af0b47?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/foundation-5.5.3.min.js?6b2ec41c18b29054?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/foundation-5.5.3.equalizer.min.js?0f6c549b75ec554c?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/jquery.multiselect.js?0edd3998731d1091?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/jquery.cycle2.min.js?63413052928f97ee?1739771134"></script> <script> // old browser fix - this way the console log rows won't throw (silent) errors in browsers not supporting console log if (!window.console) window.console = {}; if (!window.console.log) window.console.log = function () { }; var currentJournalNameSystem = "jfb"; $(document).ready(function() { $('select.foundation-select').multiselect({ search: true, minHeight: 130, maxHeight: 130, }); $(document).foundation({ orbit: { timer_speed: 4000, }, reveal: { animation: 'fadeAndPop', animation_speed: 100, } }); $(".chosen-select").each(function(element) { var maxSelected = (undefined !== $(this).data('maxselectedoptions') ? $(this).data('maxselectedoptions') : 100); $(this).on('chosen:ready', function(event, data) { var select = $(data.chosen.form_field); if (select.attr('id') === 'journal-browser-volume') { $(data.chosen.dropdown).addClass('UI_JournalBrowser_Volume_Options'); } if (select.attr('id') === 'journal-browser-issue') { $(data.chosen.dropdown).addClass('UI_JournalBrowser_Issue_Options'); } }).chosen({ display_disabled_options: false, disable_search_threshold: 7, max_selected_options: maxSelected, width: "100%" }); }); $(".toEncode").each(function(e) { var oldHref = $(this).attr("href"); var newHref = oldHref.replace('.botdefense.please.enable.javascript.','@'); $(this).attr("href", newHref); if (!$(this).hasClass("emailCaptcha")) { $(this).html(newHref.replace('mailto:', '')); } $(this).removeClass("visibility-hidden"); }); $(document).on('opened.fndtn.reveal', '[data-reveal]', function() { $(document).foundation('equalizer', 'reflow'); }); // fix the images that have tag height / width defined // otherwise the default foundation styles overwrite the tag definitions $("img").each(function() { if ($(this).attr('width') != undefined || $(this).attr('height') != undefined) { $(this).addClass("img-fixed"); } }); $("#basic_search, #advanced_search").submit(function(e) { var searchArguments = false; $(this).find("input,select").not("#search,.search-button").each(function() { if (undefined === $(this).val() || "" === $(this).val()) { $(this).attr('name', null); } else { $(this).attr('name'); searchArguments = true; } }); if (!searchArguments) { window.location = $(this).attr('action'); return false; } }); $(".hide-show-desktop-option").click(function(e) { e.preventDefault(); var parentDiv = $(this).closest("div"); $.ajax({ url: $(this).attr('href'), success: function(msg) { parentDiv.removeClass().hide(); } }); }); $(".generic-toggleable-header").click(function(e) { $(this).toggleClass("active"); $(this).next(".generic-toggleable-content").toggleClass("active"); }); /* * handle whole row as a link if the row contains only one visible link */ $("table.new tr").hover(function() { if ($(this).find("td:visible a").length == 1) { $(this).addClass("single-link"); } }, function() { $(this).removeClass("single-link"); }); $("table.new:not(.table-of-tables)").on("click", "tr.single-link", function(e) { var target = $(e.target); if (!e.ctrlKey && !target.is("a")) { $(this).find("td:visible a")[0].click(); } }); $(document).on("click", ".custom-accordion-for-small-screen-link", function(e) { if ($(this).closest("#basic_search").length > 0) { if ($(".search-container__advanced").first().is(":visible")) { openAdvanced() } } if (Foundation.utils.is_small_only()) { if ($(this).hasClass("active")) { $(this).removeClass("active"); $(this).next(".custom-accordion-for-small-screen-content").addClass("show-for-medium-up"); } else { $(this).addClass("active"); $(this).next(".custom-accordion-for-small-screen-content").removeClass("show-for-medium-up"); $(document).foundation('orbit', 'reflow'); } } if (undefined !== $(this).data("callback")) { var customCallback = $(this).data("callback"); func = window[customCallback]; func(); } }); $(document).on("click", ".js-open-small-search", function(e) { e.preventDefault(); $(this).toggleClass("active").closest(".tab-bar").toggleClass("active"); $(".search-container").toggleClass("hide-for-small-down"); }); $(document).on("click", ".js-open-menu", function(e) { $(".search-container").addClass("hide-for-small-down"); }); $(window).on('resize', function() { recalculate_main_browser_position(); recalculate_responsive_moving_containers(); }); updateSearchLabelVisibilities(); recalculate_main_browser_position(); recalculate_responsive_moving_containers(); if (window.document.documentMode == 11) { $("<link/>", { rel: "stylesheet", type: "text/css", href: "https://fonts.googleapis.com/icon?family=Material+Icons"}).appendTo("head"); } }); function recalculate_main_browser_position() { if (Foundation.utils.is_small_only()) { if ($("#js-main-top-container").parent("#js-large-main-top-container").length > 0) { $("#js-main-top-container").appendTo($("#js-small-main-top-container")); } } else { if ($("#js-main-top-container").parent("#js-small-main-top-container").length > 0) { $("#js-main-top-container").appendTo($("#js-large-main-top-container")); } } } function recalculate_responsive_moving_containers() { $(".responsive-moving-container.large").each(function() { var previousParent = $(".responsive-moving-container.active[data-id='"+$(this).data("id")+"']"); var movingContent = previousParent.html(); if (Foundation.utils.is_small_only()) { var currentParent = $(".responsive-moving-container.small[data-id='"+$(this).data("id")+"']"); } else if (Foundation.utils.is_medium_only()) { var currentParent = $(".responsive-moving-container.medium[data-id='"+$(this).data("id")+"']"); } else { var currentParent = $(".responsive-moving-container.large[data-id='"+$(this).data("id")+"']"); } if (previousParent.attr("class") !== currentParent.attr("class")) { currentParent.html(movingContent); previousParent.html(); currentParent.addClass("active"); previousParent.removeClass("active"); } }); } // cookies allowed is checked from a) local storage and b) from server separately so that the footer bar doesn't // get included in the custom page caches function checkCookiesAllowed() { var cookiesEnabled = localStorage.getItem("mdpi_cookies_enabled"); if (null === cookiesEnabled) { $.ajax({ url: "/ajax_cookie_value/mdpi_cookies_accepted", success: function(data) { if (data.value) { localStorage.setItem("mdpi_cookies_enabled", true); checkDisplaySurvey(); } else { $(".js-allow-cookies").show(); } } }); } else { checkDisplaySurvey(); } } function checkDisplaySurvey() { } window.addEventListener('CookiebotOnAccept', function (e) { var CookieDate = new Date; if (Cookiebot.consent.preferences) { CookieDate.setFullYear(CookieDate.getFullYear() + 1); document.cookie = "mdpi_layout_type_v2=mobile; path=/; expires=" + CookieDate.toUTCString() + ";"; $(".js-toggle-desktop-layout-link").css("display", "inline-block"); } }, false); window.addEventListener('CookiebotOnDecline', function (e) { if (!Cookiebot.consent.preferences) { $(".js-toggle-desktop-layout-link").hide(); if ("" === "desktop") { window.location = "/toggle_desktop_layout_cookie"; } } }, false); var hash = $(location).attr('hash'); if ("#share" === hash) { if (1 === $("#main-share-modal").length) { $('#main-share-modal').foundation('reveal', 'open'); } } </script> <script src="https://pub.mdpi-res.com/assets/js/lib.js?b86ef680a60436c6?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/mdpi.js?c267ce58392b15da?1739771134"></script> <script>var banners_url = 'https://serve.mdpi.com';</script> <script type='text/javascript' src='https://pub.mdpi-res.com/assets/js/ifvisible.min.js?c621d19ecb761212?1739771134'></script> <script src="https://pub.mdpi-res.com/assets/js/xmltohtml/affix.js?ac4ea55275297c15?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/clipboard.min.js?3f3688138a1b9fc4?1739771134"></script> <script type="text/javascript"> $(document).ready(function() { var helpFunctions = $(".middle-column__help__fixed"); var leftColumnAffix = $(".left-column__fixed"); var middleColumn = $("#middle-column"); var clone = null; helpFunctions.affix({ offset: { top: function() { return middleColumn.offset().top - 8 - (Foundation.utils.is_medium_only() ? 30 : 0); }, bottom: function() { return $("#footer").innerHeight() + 74 + (Foundation.utils.is_medium_only() ? 0 : 0); } } }); if (leftColumnAffix.length > 0) { clone = leftColumnAffix.clone(); clone.addClass("left-column__fixed__affix"); clone.insertBefore(leftColumnAffix); clone.css('width', leftColumnAffix.outerWidth() + 50); clone.affix({ offset: { top: function() { return leftColumnAffix.offset().top - 30 - (Foundation.utils.is_medium_only() ? 50 : 0); }, bottom: function() { return $("#footer").innerHeight() + 92 + (Foundation.utils.is_medium_only() ? 0 : 0); } } }); } $(window).on("resize", function() { if (clone !== null) { clone.css('width', leftColumnAffix.outerWidth() + 50); } }); new ClipboardJS('.js-clipboard-copy'); }); </script> <script src="https://pub.mdpi-res.com/assets/js/jquery-ui-1.13.2.min.js?1e2047978946a1d2?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/slick.min.js?d5a61c749e44e471?1739771134"></script> <script> $(document).ready(function() { $(".link-article-menu").click(function(e) { e.preventDefault(); $(this).find('span').toggle(); $(this).next("div").toggleClass("active"); }); $(".js-similarity-related-articles").click(function(e) { e.preventDefault(); if ('' !== $('#recommended-articles-modal').attr('data-url')) { $('#recommended-articles-modal').foundation('reveal', 'open', $('#recommended-articles-modal').attr('data-url')); } }); $.ajax({ url: "/article/1492689/similarity-related/show-link", success: function(result) { if (result.show) { $('#recommended-articles-modal').attr('data-url', result.link); $('.js-article-similarity-container').show(); } } }); $("#recommended-articles-modal").on("click", ".ga-title-link-recommended-article", function(e) { var clickEventUrl = $(this).data("click-event-url"); if (typeof clickEventUrl !== "undefined") { fetch(clickEventUrl, { method: "GET", mode: "no-cors" }); } }); $(document).on('opened.fndtn.reveal', '[data-reveal]', function() { var modal = $(this); if (modal.attr('id') === "author-biographies-modal") { modal.find('.multiple-items').slick({ slidesToShow: 1, nextArrow: '<a class="slick-next" href="#"><i class="material-icons">chevron_right</i></a>', prevArrow: '<a class="slick-prev" href="#"><i class="material-icons">chevron_left</i></a>', slidesToScroll: 1, draggable: false, }); modal.find('.multiple-items').slick('refresh'); } }); }); </script> <script type="text/javascript"> if (-1 !== window.location.href.indexOf("?src=")) { window.history.replaceState({}, '', `${location.pathname}`); } $(document).ready(function() { var scifeedCounter = 0; var search = window.location.search; var mathjaxReady = false; // late image file loading $("img[data-lsrc]").each(function() { $(this).attr("src", $(this).data("lsrc")); }); // late mathjax initialization var head = document.getElementsByTagName("head")[0]; var script = document.createElement("script"); script.type = "text/x-mathjax-config"; script[(window.opera ? "innerHTML" : "text")] = "MathJax.Hub.processSectionDelay = 0;\n" + "MathJax.Hub.Config({\n" + " \"menuSettings\": {\n" + " CHTMLpreview: false\n" + " },\n" + " \"CHTML-preview\":{\n" + " disabled: true\n" + " },\n" + " \"HTML-CSS\": {\n" + " scale: 90,\n" + " availableFonts: [],\n" + " preferredFont: null,\n" + " preferredFonts: null,\n" + " webFont:\"Gyre-Pagella\",\n" + " imageFont:'TeX',\n" + " undefinedFamily:\"'Arial Unicode MS',serif\",\n" + " linebreaks: { automatic: false }\n" + " },\n" + " \"TeX\": {\n" + " extensions: ['noErrors.js'],\n" + " noErrors: {\n" + " inlineDelimiters: [\"\",\"\"],\n" + " multiLine: true,\n" + " style: {\n" + " 'font-size': '90%',\n" + " 'text-align': 'left',\n" + " 'color': 'black',\n" + " 'padding': '1px 3px',\n" + " 'border': '1px solid'\n" + " }\n" + " }\n" + " }\n" + "});\n" + "MathJax.Hub.Register.StartupHook('End', function() {\n" + " refreshMathjaxWidths();\n" + " mathjaxReady = true;\n" + "});\n" + "MathJax.Hub.Startup.signal.Interest(function (message) {\n" + " if (message == 'End') {\n" + " var hypoLink = document.getElementById('hypothesis_frame');\n" + " if (null !== hypoLink) {\n" + " hypoLink.setAttribute('src', 'https://commenting.mdpi.com/embed.js');\n" + " }\n" + " }\n" + "});"; head.appendChild(script); script = document.createElement("script"); script.type = "text/javascript"; script.src = "https://pub.mdpi-res.com/bundles/mathjax/MathJax.js?config=TeX-AMS-MML_HTMLorMML"; head.appendChild(script); // article version checker if (0 === search.indexOf('?type=check_update&version=')) { $.ajax({ url: "/2079-4983/15/10/297" + "/versioncheck" + search, success: function(result) { $(".js-check-update-container").html(result); } }); } $('#feed_option').click(function() { // tracker if ($('#scifeed_clicked').length<1) { $(this).append('<span style="display:none" id="scifeed_clicked">done</span>'); } $('#feed_data').toggle('slide', { direction: 'up'}, '1000'); // slideToggle(700); OR toggle(700) $("#scifeed_error_msg").html('').hide(); $("#scifeed_notice_msg").html('').hide(); }); $('#feed_option').click(function(event) { setTimeout(function(){ var captchaSection = $("#captchaSection"); captchaSection.removeClass('ui-helper-hidden').find('input').prop('disabled', false); // var img = captchaSection.find('img'); // img.attr('src', img.data('url') + "?" + (new Date()).getTime()); // $(".captcha_reload").trigger("click"); var img = document.getElementById('gregwar_captcha_scifeed'); img.src = '/generate-captcha/gcb_captcha?n=' + (new Date()).getTime(); },800); }); $(document).on('click', '.split_feeds', function() { var name = $( this ).attr('name'); var flag = 1 - ($(this).is(":checked")*1); $('.split_feeds').each(function (index) { if ($( this ).attr('name') !== name) { $(this)[0].checked = flag; } }); }); $(document).on('click', '#scifeed_submit, #scifeed_submit1', function(event) { event.preventDefault(); $(".captcha_reload").trigger("click"); $("#scifeed_error_msg").html(""); $("#scifeed_error_msg").hide(); }); $(document).on('click', '.subscription_toggle', function(event) { if ($(this).val() === 'Create SciFeed' && $('#scifeed_hidden_flag').length>0) { event.preventDefault(); // alert('Here there would be a captcha because user is not logged in'); var captchaSection = $("#captchaSection"); if (captchaSection.hasClass('ui-helper-hidden')) { captchaSection.removeClass('ui-helper-hidden').find('input').prop('disabled', false); var img = captchaSection.find('img'); img.attr('src', img.data('url') + "?" + (new Date()).getTime()); $("#reloadCaptcha").trigger("click"); } } }); $(document).on('click', '.scifeed_msg', function(){ $(this).hide(); }); $(document).on('click', '.article-scilit-search', function(e) { e.preventDefault(); var data = $(".article-scilit-search-data").val(); var dataArray = data.split(';').map(function(keyword) { return "(\"" + keyword.trim() + "\")"; }); var searchQuery = dataArray.join(" OR "); var searchUrl = encodeURI("https://www.scilit.com/articles/search?q="+ searchQuery + "&advanced=1&highlight=1"); var win = window.open(searchUrl, '_blank'); if (win) { win.focus(); } else { window.location(searchUrl); } }); display_stats(); citedCount(); follow_goto(); // Select the node that will be observed for mutations const targetNodes = document.getElementsByClassName('hypothesis-count-container'); // Options for the observer (which mutations to observe) const config = { attributes: false, childList: true, subtree: false }; // Callback function to execute when mutations are observed const callback = function(mutationList, observer) { for(const mutation of mutationList) { if (mutation.type === 'childList') { let node = $(mutation.target); if (parseInt(node.html()) > 0) { node.show(); } } } }; // Create an observer instance linked to the callback function const observer = new MutationObserver(callback); // Start observing the target node for configured mutations for(const targetNode of targetNodes) { observer.observe(targetNode, config); } // Select the node that will be observed for mutations const mathjaxTargetNode = document.getElementById('middle-column'); // Callback function to execute when mutations are observed const mathjaxCallback = function(mutationList, observer) { if (mathjaxReady && typeof(MathJax) !== 'undefined') { refreshMathjaxWidths(); } }; // Create an observer instance linked to the callback function const mathjaxObserver = new ResizeObserver(mathjaxCallback); // Start observing the target node for configured mutations mathjaxObserver.observe(mathjaxTargetNode); }); /* END $(document).ready */ function refreshMathjaxWidths() { let width = ($('.html-body').width()*0.9) + "px"; $('.MathJax_Display').css('max-width', width); $('.MJXc-display').css('max-width', width); } function sendScifeedFrom(form) { if (!$('#scifeed_email').val().trim()) { // empty email alert('Please, provide an email for subscribe to this scifeed'); return false; } else if (!$('#captchaSection').hasClass('ui-helper-hidden') && !$('#captchaSection').find('input').val().trim()) { // empty captcha alert('Please, fill the captcha field.'); return false; } else if( ((($('#scifeed_form').find('input:checkbox:checked').length)-($('#split_feeds:checked').length))<1) || ($('#scifeed_kwd_txt').length < 0 && !$('#scifeed_kwd_txt').val().trim()) || ($('#scifeed_author_txt').length<0 &&!$('#scifeed_author_txt').val().trim()) ) { alert('You did not select anything to subscribe'); return false; } else if(($('#scifeed_form').find('input:checkbox:checked').length)-($('#split_feeds2:checked').length)<1){ alert("You did not select anything to subscribe"); return false; } else { var url = $('#scifeed_subscribe_url').html(); var formData = $(form).serializeArray(); $.post(url, formData).done(function (data) { if (JSON.parse(data)) { $('.scifeed_msg').hide(); var res = JSON.parse(data); var successFeeds = 0; var errorFeeds = 0; if (res) { $('.scifeed_msg').html(''); $.each(res, function (index, val) { if (val) { if (val.error) { errorFeeds++; $("#scifeed_error_msg").append(index+' - '+val.error+'<br>'); } if (val.notice) // for successful feed creation { successFeeds++; // $("#scifeed_notice_msg").append(index+' - '+val.notice+'<br>'); $("#scifeed_notice_msg").append('<li>'+index+'</li>'); } } }); if (successFeeds>0) { text = $('#scifeed_notice_msg').html(); text = 'The following feed'+(successFeeds>1?'s have':' has')+ ' been sucessfully created:<br><ul>'+ text + '</ul>' +($('#scifeed_hidden_flag').length>0 ? 'You are not logged in, so you probably need to validate '+ (successFeeds>1?'them':' it')+'.<br>' :'' ) +'Please check your email'+(successFeeds>1?'s':'')+' for more details.'; //(successFeeds>1?' for each of them':'')+'.<br>'; $("#scifeed_notice_msg").html(text); $("#scifeed_notice_msg").show(); } if (errorFeeds>0) { $("#scifeed_error_msg").show();; } } $("#feed_data").hide(); } }); } } function follow_goto() { var hashStr = location.hash.replace("#",""); if(typeof hashStr !== 'undefined') { if( hashStr == 'supplementary') { document.getElementById('suppl_id').scrollIntoView(); } if( hashStr == 'citedby') { document.getElementById('cited_id').scrollIntoView(); } } } function cited() { $("#framed_div").toggle('fast', function(){ if ($(this).css('display') != 'none') { var loaded = document.getElementById("loaded"); if(loaded.innerHTML == "No") { // Load Xref result var container = document.getElementById("framed_div"); // This replace the content container.innerHTML = "<img src=\"https://pub.mdpi-res.com/img/loading_circle.gif?9a82694213036313?1739771134\" height=\"20\" width=\"20\" alt=\"Processing...\" style=\"vertical-align:middle; margin-right:0.6em;\">"; var url = "/citedby/10.3390%252Fjfb15100297/104"; $.post(url, function(result) { if (result.success) { container.innerHTML = result.view; } loaded.innerHTML = "Yes"; }); } } return true; // for not going at the beginning of the page... }) return true; // for not going at the beginning of the page... } function detect_device() { // Added by Bastien (18/08/2014): based on the http://detectmobilebrowsers.com/ detector var check = false; (function(a){if(/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|mobile.+firefox|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino/i.test(a)||/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i.test(a.substr(0,4)))check = true})(navigator.userAgent||navigator.vendor||window.opera); return check; } function display_stats(){ $("#article_stats_div").toggle(); return false; } /* * Cited By Scopus */ function citedCount(){ $("#framed_div_cited_count").toggle('fast', function(){ if ($(this).css('display') != 'none') { var loaded = document.getElementById("loaded_cite_count"); // to load only once the result! if(loaded.innerHTML == "No") { // Load Xref result var d = document.getElementById("framed_div_cited_count"); // This replace the content d.innerHTML = "<img src=\"https://pub.mdpi-res.com/img/loading_circle.gif?9a82694213036313?1739771134\" height=\"20\" width=\"20\" alt=\"Processing...\" style=\"vertical-align:middle; margin-right:0.6em;\">"; $.ajax({ method : "POST", url : "/cite-count/10.3390%252Fjfb15100297", success : function(data) { if (data.succ) { d.innerHTML = data.view; loaded.innerHTML = "Yes"; follow_goto(); } } }); } } // end else return true; // for not going at the beginning of the page... }) return true; // for not going at the beginning of the page... } </script><script type="text/javascript" src="https://pub.mdpi-res.com/assets/js/third-party/highcharts/highcharts.js?bdd06f45e34c33df?1739771134"></script><script type="text/javascript" src="https://pub.mdpi-res.com/assets/js/third-party/highcharts/modules/exporting.js?944dc938d06de3a8?1739771134"></script><script type="text/javascript" defer="defer"> var advancedStatsData; var selectedStatsType = "abstract"; $(function(){ var countWrapper = $('#counts-wrapper'); $('#author_stats_id #type_links a').on('click', function(e) { e.preventDefault(); selectedStatsType = $(this).data('type'); $('#article_advanced_stats').vectorMap('set', 'values', advancedStatsData[selectedStatsType]); $('#advanced_stats_max').html(advancedStatsData[selectedStatsType].max); $('#type_links a').removeClass('active'); $(this).addClass('active'); }); $.get('/2079-4983/15/10/297/stats', function (result) { if (!result.success) { return; } // process article metrics part in left column var viewNumber = countWrapper.find(".view-number"); viewNumber.html(result.metrics.views); viewNumber.parent().toggleClass("count-div--grey", result.metrics.views == 0); var downloadNumber = countWrapper.find(".download-number"); downloadNumber.html(result.metrics.downloads); downloadNumber.parent().toggleClass("count-div--grey", result.metrics.downloads == 0); var citationsNumber = countWrapper.find(".citations-number"); citationsNumber.html(result.metrics.citations); citationsNumber.parent().toggleClass("count-div--grey", result.metrics.citations == 0); if (result.metrics.views > 0 || result.metrics.downloads > 0 || result.metrics.citations > 0) { countWrapper.find("#js-counts-wrapper__views, #js-counts-wrapper__downloads").addClass("visible").show(); if (result.metrics.citations > 0) { countWrapper.find('.citations-number').html(result.metrics.citations).show(); countWrapper.find("#js-counts-wrapper__citations").addClass("visible").show(); } else { countWrapper.find("#js-counts-wrapper__citations").remove(); } $("[data-id='article-counters']").removeClass("hidden"); } if (result.metrics.altmetrics_score > 0) { $("#js-altmetrics-donut").show(); } // process view chart in main column var jsondata = result.chart; var series = new Array(); $.each(jsondata.elements, function(i, element) { var dataValues = new Array(); $.each(element.values, function(i, value) { dataValues.push(new Array(value.tip, value.value)); }); series[i] = {name: element.text, data:dataValues}; }); Highcharts.setOptions({ chart: { style: { fontFamily: 'Arial,sans-serif' } } }); $('#article_stats_swf').highcharts({ chart: { type: 'line', width: $("#tabs").width() //* 0.91 }, credits: { enabled: false }, exporting: { enabled: true }, title: { text: jsondata.title.text, x: -20 //center }, xAxis: { categories: jsondata.x_axis.labels.labels, offset: jsondata.x_axis.offset, labels:{ step: jsondata.x_axis.labels.steps, rotation: 30 } }, yAxis: { max: jsondata.y_axis.max, min: jsondata.y_axis.min, offset: jsondata.y_axis.offset, labels: { steps: jsondata.y_axis.steps }, title: { enabled: false } }, tooltip: { formatter: function (){ return this.key.replace("#val#", this.y); } }, legend: { align: 'top', itemDistance: 50 }, series: series }); }); $('#supplement_link').click(function() { document.getElementById('suppl_id').scrollIntoView(); }); $('#stats_link').click(function() { document.getElementById('stats_id').scrollIntoView(); }); // open mol viewer for molbank special supplementary files $('.showJmol').click(function(e) { e.preventDefault(); var jmolModal = $("#jmolModal"); var url = "/article/1492689/jsmol_viewer/__supplementary_id__"; url = url.replace(/__supplementary_id__/g, $(this).data('index')); $('#jsmol-content').attr('src', url); jmolModal.find(".content").html($(this).data('description')); jmolModal.foundation("reveal", "open"); }); }); !function() { "use strict"; function e(e) { try { if ("undefined" == typeof console) return; "error"in console ? console.error(e) : console.log(e) } catch (e) {} } function t(e) { return d.innerHTML = '<a href="' + e.replace(/"/g, """) + '"></a>', d.childNodes[0].getAttribute("href") || "" } function n(n, c) { var o = ""; var k = parseInt(n.substr(c + 4, 2), 16); for (var i = c; i < n.length; i += 2) { if (i != c + 4) { var s = parseInt(n.substr(i, 2), 16) ^ k; o += String.fromCharCode(s); } } try { o = decodeURIComponent(escape(o)); } catch (error) { console.error(error); } return t(o); } function c(t) { for (var r = t.querySelectorAll("a"), c = 0; c < r.length; c++) try { var o = r[c] , a = o.href.indexOf(l); a > -1 && (o.href = "mailto:" + n(o.href, a + l.length)) } catch (i) { e(i) } } function o(t) { for (var r = t.querySelectorAll(u), c = 0; c < r.length; c++) try { var o = r[c] , a = o.parentNode , i = o.getAttribute(f); if (i) { var l = n(i, 0) , d = document.createTextNode(l); a.replaceChild(d, o) } } catch (h) { e(h) } } function a(t) { for (var r = t.querySelectorAll("template"), n = 0; n < r.length; n++) try { i(r[n].content) } catch (c) { e(c) } } function i(t) { try { c(t), o(t), a(t) } catch (r) { e(r) } } var l = "/cnd-cgi/l/email-protection#" , u = ".__cf_email__" , f = "data-cfemail" , d = document.createElement("div"); i(document), function() { var e = document.currentScript || document.scripts[document.scripts.length - 1]; e.parentNode.removeChild(e) }() }(); </script><script type="text/javascript"> function setCookie(cname, cvalue, ctime) { ctime = (typeof ctime === 'undefined') ? 10*365*24*60*60*1000 : ctime; // default => 10 years var d = new Date(); d.setTime(d.getTime() + ctime); // ==> 1 hour = 60*60*1000 var expires = "expires="+d.toUTCString(); document.cookie = cname + "=" + cvalue + "; " + expires +"; path=/"; } function getCookie(cname) { var name = cname + "="; var ca = document.cookie.split(';'); for(var i=0; i<ca.length; i++) { var c = ca[i]; while (c.charAt(0)==' ') c = c.substring(1); if (c.indexOf(name) == 0) return c.substring(name.length, c.length); } return ""; } </script><script type="text/javascript" src="https://d1bxh8uas1mnw7.cloudfront.net/assets/embed.js"></script><script> $(document).ready(function() { if ($("#js-similarity-related-data").length > 0) { $.ajax({ url: '/article/1492689/similarity-related', success: function(response) { $("#js-similarity-related-data").html(response); $("#js-related-articles-menu").show(); $(document).foundation('tab', 'reflow'); MathJax.Hub.Queue(["Typeset", MathJax.Hub]); } }); } }); </script><link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/jquery-ui-1.10.4.custom.min.css?80647d88647bf347?1739771134"><link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/magnific-popup.min.css?04d343e036f8eecd?1739771134"><script type="text/javascript" src="https://pub.mdpi-res.com/assets/js/magnific-popup.min.js?2be3d9e7dc569146?1739771134"></script><script> $(function() { $(".js-show-more-academic-editors").on("click", function(e) { e.preventDefault(); $(this).hide(); $(".academic-editor-container").removeClass("hidden"); }); }); </script> <link rel="stylesheet" href="https://pub.mdpi-res.com/assets/css/vmap/jqvmap.min.css?126a06688aa11c13?1739771134"> <script src="https://pub.mdpi-res.com/assets/js/vmap/jquery.vmap.min.js?935f68d33bdd88a1?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/vmap/jquery.vmap.world.js?16677403c0e1bef1?1739771134"></script> <script> function updateSlick() { $('.multiple-items').slick('setPosition'); } $(document).ready(function() { $('.multiple-items').slick({ slidesToShow: 1, nextArrow: '<a class="slick-next" href="#"><i class="material-icons">chevron_right</i></a>', prevArrow: '<a class="slick-prev" href="#"><i class="material-icons">chevron_left</i></a>', slidesToScroll: 1, responsive: [ { breakpoint: 1024, settings: { slidesToShow: 1, slidesToScroll: 1, } }, { breakpoint: 600, settings: { slidesToShow: 1, slidesToScroll: 1, } }, { breakpoint: 480, settings: { slidesToShow: 1, slidesToScroll: 1, } } ] }); $('.multiple-items').show(); $(document).on('click', '.reviewReportSelector', function(e) { let path = $(this).attr('data-path'); handleReviews(path, $(this)); }); $(document).on('click', '.viewReviewReports', function(e) { let versionOne = $('#versionTab_1'); if (!versionOne.hasClass('activeTab')) { let path = $(this).attr('data-path'); handleReviews(path, versionOne); } location.href = "#reviewReports"; }); $(document).on('click', '.reviewersResponse, .authorResponse', function(e) { let version = $(this).attr('data-version'); let targetVersion = $('#versionTab_' + version); if (!targetVersion.hasClass('activeTab')) { let path = targetVersion.attr('data-path'); handleReviews(path, targetVersion); } location.href = $(this).attr('data-link'); }); $(document).on('click', '.tab', function (e) { e.preventDefault(); $('.tab').removeClass('activeTab'); $(this).addClass('activeTab') $('.tab').each(function() { $(this).closest('.tab-title').removeClass('active'); }); $(this).closest('.tab-title').addClass('active') }); }); function handleReviews(path, target) { $.ajax({ url: path, context: this, success: function (data) { $('.activeTab').removeClass('activeTab'); target.addClass('activeTab'); $('#reviewSection').html(data.view); }, error: function (xhr, ajaxOptions, thrownError) { console.log(xhr.status); console.log(thrownError); } }); } </script> <script src="https://pub.mdpi-res.com/assets/js/xmltohtml/affix.js?v1?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/xmltohtml/storage.js?e9b262d3a3476d25?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/xmltohtml/jquery-scrollspy.js?09cbaec0dbb35a67?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/xmltohtml/magnific-popup.js?4a09c18460afb26c?1739771134"></script> <script src="https://pub.mdpi-res.com/assets/js/xmltohtml/underscore.js?f893e294cde60c24?1739771134"></script> <script type="text/javascript"> $('document').ready(function(){ $("#left-column").addClass("show-for-large-up"); $("#middle-column").removeClass("medium-9").removeClass("left-bordered").addClass("medium-12"); $(window).on('resize scroll', function() { /* if ($('.button--drop-down').isInViewport($(".top-bar").outerHeight())) { */ if ($('.button--drop-down').isInViewport()) { $("#js-button-download").hide(); } else { $("#js-button-download").show(); } }); }); $(document).on('DOMNodeInserted', function(e) { var element = $(e.target); if (element.hasClass('menu') && element.hasClass('html-nav') ) { element.addClass("side-menu-ul"); } }); </script> <script src="https://pub.mdpi-res.com/assets/js/xmltohtml/articles.js?5118449d9ad8913a?1739771134"></script> <script> repositionOpenSideBar = function() { $('#left-column').addClass("show-for-large-up show-for-medium-up").show(); $('#middle-column').removeClass('large-12').removeClass('medium-12'); $('#middle-column').addClass('large-9'); } repositionCloseSideBar = function() { $('#left-column').removeClass("show-for-large-up show-for-medium-up").hide(); $('#middle-column').removeClass('large-9'); $('#middle-column').addClass('large-12').addClass('medium-12'); } </script>   <script type="text/plain" data-cookieconsent="marketing"> !function(e,t,n,s,u,a){e.twq||(s=e.twq=function(){s.exe?s.exe.apply(s,arguments):s.queue.push(arguments); },s.version='1.1',s.queue=[],u=t.createElement(n),u.async=!0,u.src='//static.ads-twitter.com/uwt.js', a=t.getElementsByTagName(n)[0],a.parentNode.insertBefore(u,a))}(window,document,'script'); // Insert Twitter Pixel ID and Standard Event data below twq('init','o2pip'); twq('track','PageView'); </script>  <script>(function(){function c(){var b=a.contentDocument||a.contentWindow.document;if(b){var d=b.createElement('script');d.innerHTML="window.__CF$cv$params={r:'91349de88dde7980',t:'MTczOTc4MzEzOS4wMDAwMDA='};var a=document.createElement('script');a.nonce='';a.src='/cdn-cgi/challenge-platform/scripts/jsd/main.js';document.getElementsByTagName('head')[0].appendChild(a);";b.getElementsByTagName('head')[0].appendChild(d)}}if(document.body){var a=document.createElement('iframe');a.height=1;a.width=1;a.style.position='absolute';a.style.top=0;a.style.left=0;a.style.border='none';a.style.visibility='hidden';document.body.appendChild(a);if('loading'!==document.readyState)c();else if(window.addEventListener)document.addEventListener('DOMContentLoaded',c);else{var e=document.onreadystatechange||function(){};document.onreadystatechange=function(b){e(b);'loading'!==document.readyState&&(document.onreadystatechange=e,c())}}}})();</script></body> </html>

CINXE.COM

3D-Printable Gelatin Methacrylate-Xanthan Gum Hydrogel Bioink Enabling Human Induced Pluripotent Stem Cell Differentiation into Cardiomyocytes