Thiol-ene Cross-Linkable Hydrogels as Bioinks for Biofabrication

This article introduces biofabrication and highlights the role of hydrogels in this field of research as materials that combine chemical tunability with cytocompatibility and the suitability for processing with biofabrication technologies. So far, chemical cross-linking as post-fabrication step to stabilize the printed structures has mainly been achieved by free radical polymerization of (meth-)acrylated hydrogel components. We discuss thiol-ene chemistry as an interesting alternative that is widely used in polymer science, but has so far not been explored much for biofabrication. We then present our development of thiol-ene cross-linkable hydrogel-bioink as alternative to the widely used free radical photopolymerization of methacrylated molecules in biofabrication. Thiol-ene chemistry allows for rapid gelation after printing with good shape fidelity and high reproducibility under identical printing parameters.