An injectable, self-healing carboxymethylated chitosan hydrogel with mild photothermal stimulation for wound healing

Hydrogels can mimic extracellular matrix and provide a suitable microenvironment for accelerating wound healing. Nevertheless, the complicated wound condition, the disturbance of external forces, and the manufacturing process of the dressing were still difficult problems. An injectable self-healing hydrogel with mild photothermal therapy (MPTT) was developed for wound healing via dynamic Schiff bonds. After covalently incorporating GO-BPEI (branched polyethyleneimine grafting graphene oxide), an observable mechanical strength improvement and photothermal conversion property of GO-BPEI/carboxymethylated chitosan (CMCS) /aldehyde terminated polyethylene glycol (PEG-CHO) (GCP) hydrogel has been witnessed. MPTT induced by near-infrared (NIR) irradiation could accelerate NIH-3 T3 cells proliferation in vitro . Moreover, in vivo wound defect healing and histological analysis suggested that GCP hydrogels incorporated with MPTT significantly accelerated wound healing by improving collagen fibers deposition, enhancing re-epithelialization, and promoting granulation tissue neogenesis. The GCP hydrogels provide a unique route for wound dressing and present new inspirations for complicated wound management.