In Situ injectable photo-crosslinking hydrogel with heterojunction nanoparticles for dual-channel synergistic disinfection and cutaneous regeneration in diabetic chronic wound healing

Recurrent inflammation, intense bacterial infections, and inadequate blood vessel growth make diabetic wounds non-healing. Under pathological environment, cellular functions are also inhibited. In this paper, we developed a novel in situ injectable photo-crosslinking hydrogel embedded with heterojunction Ag@ZnO nanoparticles (NPs) which exhibit dual-channel synergistic ion release and reactive oxygen species (ROS) production for anti-bacteria and cutaneous regeneration. This novel hydrogel platform can be introduced onto any irregular wound and form gelation with 395 nm UV light irradiation in only 5 s. After being affixed to the wound, Ag+ and Zn2+ can be released as the first interaction for wound healing. Foremost, the heterojunction formed on interface of Ag and ZnO has the ability to capture oxygen and water to instigate the generation of a "ROS storm", which can disrupt the structural integrity of bacteria, trigger the leakage of bacterial cytoplasmic content, enhance angiogenesis by activating VEGF and CD31 expression, and stimulate the steps of wound healing. The continuous release of Ag+, Zn2+ and "ROS storm" collaboratively drive bacterial deactivation, suppress inflammation, promote cellular proliferation, collagen deposition and angiogenesis. These effects significantly accelerate diabetic chronic wounds healing. Therefore, such dual-channel synergistic hydrogel platform might provide a promising new insight to diabetic chronic wound treatment.