Photodegradable Gelatin-Based Hydrogels Prepared by Bioorthogonal Click Chemistry for Cell Encapsulation and Release

In this study, we present a method for the fabrication of in situ forming gelatin and poly­(ethylene glycol)-based hydrogels utilizing bioorthogonal, strain-promoted alkyne–azide cycloaddition as the cross-linking reaction. By incorporating nitrobenzyl moieties within the network structure, these hydrogels can be designed to be degradable upon irradiation with low intensity UV light, allowing precise photopatterning. Fibroblast cells encapsulated within these hydrogels were viable at 14 days and could be readily harvested using a light trigger. Potential applications of this new class of injectable hydrogel include its use as a 3D culturing platform that allows the capture and release of cells, as well as light-triggered cell delivery in regenerative medicine.