Multifunctional Hydrogel Containing Oxygen Vacancy-Rich WO_x for Synergistic Photocatalytic O₂ Production and Photothermal Therapy Promoting Bacteria-Infected Diabetic Wound Healing

An effective method capable of simultaneously providing antibacterial activity, blood glucose regulation, and angiogenesis promotion for healing bacteria-infected diabetic wounds is not reported to date, but urgently required. In this study, a hydrogel composite (γ-PGA/PDA/GOx/WO_x (PPGW)), endowed with these desired attributes is fabricated by incorporating polydopamine (PDA), glucose oxidase (GOx), and tungsten oxide (WO_x) nanowires into the poly(γ-glutamic acid) (γ-PGA) framework. The exceptional photothermal conversion properties of PDA facilitated notable antibacterial effects on bacteria-infected diabetic wounds; GOx regulated high blood glucose by consuming glucose and generating hydrogen peroxide (H₂O₂); while WO_x nanowires displayed remarkable photocatalytic abilities, converting H₂O₂ into oxygen (O₂) when exposed to 808-nm near-infrared radiation. Density functional theory calculations and experiments are conducted to confirm the mechanism of WO_x-mediated photocatalytic degradation of H₂O₂ to produce O₂. These transformations aided in alleviating the hypoxic conditions in wounds associated with diabetes, expediting angiogenesis, and fostering cell crawling and proliferation. Consequently, the multifunctional hydrogel dressing PPGW, featuring photothermal, antibacterial, and enzyme-catalyzed activity reduces hyperglycemia at the wound site. Moreover, photocatalytic O₂ production represents a promising strategy for addressing chronic bacteria-infected diabetic wounds.