Hydrolytically degradable thiol-ene hydrogels for protein release

A new degradable PEG-diester-dinorbornene/PEG-triester-trithiol hydrogel was evaluated for protein release. The hydrogel polymerized rapidly with seconds of UV irradiation and subsequently hydrolytically degraded in aqueous buffer over the course of approximately 3 weeks. Further, the hydrogel enabled the encapsulation and release of a model protein, bovine serum albumin (BSA), over 7 days with ~ 90% released at 48 h. This study serves as a proof-of-concept for the creation of hydrolytically degradable, PEG-ester-thiol-based hydrogels by a photoinitiated step growth mechanism for protein release. With this approach, degradation and release rates could be tuned by varying the monomer molecular weight and functionality in future studies.