All-natural hydrogel composed of carboxymethyl chitosan and oxidized dextran for promoting wound healing by immune-microenvironment regulation.

Chronic wound treatment has always been a major clinical challenge owing to complex and dynamic wound microenvironment. The design and development of effective management with antimicrobial activity, ROS-scavenging and regulation immune response is vital for tissue repair. Herein, we developed puerarin (PUE) loaded a double network hydrogel consisting of methacrylated carboxymethyl chitosan and oxidized dextran with Schiff base and photo-crosslinking reaction. The composite hydrogel presented fast self-healing and outstanding compressive performance to bear deformation. The hydrogel exhibits a cumulative drug release pattern with biphasic release, which offers great potential for accelerating tissue healing at all stages of wounding. In addition, the hydrogel has good biocompatibility, antimicrobial ability and tube-forming ability in vitro. The full-thickness skin wound model of Staphylococcus aureus infection showed that the hydrogel dressing can accelerate tissue repair. This study demonstrated that the design of combing natural biomacromolecules with traditional Chinese medicine could be severed as a promising candidate biomaterial for skin tissue recovery.