Cationic injectable hydrogels for wet-tissue sealing with enhanced red blood cell retention.

A cationic injectable hydrogel was constructed from thiolated hyaluronic acid and acrylate-functionalised hyperbranched poly(ethylene glycol) via thiol-Michael addition, with covalently immobilised quaternary ammonium groups. The resulting network showed rapid gelation within 27-45 s, tuneable wet-tissue sealing, enzyme-responsive wet-mass loss, enhanced red blood cell retention and good cytocompatibility after network formation.