Enzyme-Fenton Cascade Reaction for Preparing GelMA Photothermal Antibacterial Hydrogels to Promote Wound Healing

Gelatin-based hydrogels are promising scaffolds for tissue engineering because of their biocompatibility and adjustable physical and chemical properties. Here, we describe a photothermal hydrogel made from gelatin methacryloyl (GelMA). Unlike UV-crosslinking methods, which can cause light-induced toxicity, gelation in this study occurs through an iron-tannic acid (Fe-TA) metal-phenolic network (MPN) that triggers an enzymatic Fenton cascade reaction. When exposed to glucose in the wound environment, glucose oxidase (GOx) produces hydrogen peroxide (H 2 O 2 ), which reacts with Fe 2+ to create reactive species that cause on-site gelation of GelMA. The resulting hydrogel shows strong biocompatibility and combined photothermal antibacterial effects under light exposure. In addition, L-arginine (L-Arg) is added in a slow-release form to actively support wound healing. This versatile system integrates in situ gelation, antimicrobial effects, and healing promotion, providing a promising approach for advanced wound care.