Self-adhesive photothermal hydrogel films for solar-light assisted wound healing

Hydrogel-based dressings can provide a moist environment for wounds, and have been proven to be beneficial for wound healing. However, preparation of effective hydrogel dressings in a facile yet robust manner still remains a big challenge. Herein, a photo-initiated polymerization method is employed to develop a photothermal hydrogel film with self-adhesive properties for accelerated wound healing under solar light irradiation. Such a hydrogel film is obtained by taking advantage of the excellent adhesion of bioinspired polydopamine (PDA) and the great photothermal conversion capability of reduced graphene oxide (rGO) upon solar light irradiation. The formed photothermal hydrogel film could adhere to wounds and convert solar light into heat, warming up the wound locally. The localized temperature enhancement significantly promotes wound healing by reducing the inflammatory response, and enhancing re-epithelialization, angiogenesis, and collagen deposition, presumably correlated with the increased expressions of transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor-A (VEGF-A). This finding demonstrates the great potential of the photothermal hydrogel film for wound healing in clinical or daily applications.