A novel injectable chitosan/polyglutamate polyelectrolyte complex hydrogel with hydroxyapatite for soft-tissue augmentation

► We developed a CS/PG PEC hydrogel combined with HAp as a novel dermal filler for soft-tissue augmentation. ► The hydrogel had a high gel content, slow degradation rate, injectability, structural integrity and biocompatibility. ► The dermal filler indicated that it had long-term stability and stimulated ingrowth of new collagen.