Thermal-Responsive Antibacterial Hydrogel with Photothermal Therapy and Improving Wound Microenvironment for Promote Healing.

Skin damage is one of the most prevalent human injuries, which affects the health of human beings. However, skin damage is often accompanied by bacterial infection and wound microenvironment changes, causing damage to normal cells and inhibiting wound healing. Herein, we designed a thermal-responsive antibacterial hydrogel (GAG hydrogel) loaded with catalase (CAT)-like Au@Pt@MgSiO nanoparticles (APM NPs) and gentamicin (GM) to promote wound healing. The GAG hydrogel was used in a photothermal therapy (PTT)/antibiotic combination to kill bacteria, reduce the use of antibiotics, improve the wound microenvironment, promote cell proliferation, and accelerate wound healing. Under near-infrared laser irradiation, APM NPs in the hydrogel generated local hyperthermia to kill bacteria. Meanwhile, the generated heat led to a change in the hydrogel's morphology, enabling it to release GM and APM NPs to prevent the overuse of antibiotics. Subsequently, the CAT-like ability of the APM NPs decreased the oxidative stress caused by hydrogen peroxide (HO), thus remodeling the wound microenvironment. Then, the weakly acidic microenvironment of the wound caused the decomposition of the APM NPs and the release of magnesium ions (Mg), promoting the growth and migration of cells for wound healing. Therefore, the studied thermal-responsive antibacterial (GAG) hydrogel has potential in the field of wound healing.