Natural polymer chitosan-based hydrogels can enhance mechanical properties and produce H2S gas by UV-light to treat scalded wound.

The healing of deep second- and third-degree scald wounds is frequently impaired by inflammation, oxidative stress, vascular damage, and neural injury, creating substantial challenges for clinical wound management. To address this, we developed a novel hydrogel dressing strategy utilizing alpha-lipoic acid-modified chitosan (LAMC) combined with a four-armed polyethylene glycol derivative (PEG-NHS). This hydrogel achieves rapid wound coverage through its inherent adhesive properties, followed by ultraviolet (UV)-triggered secondary cross-linking to enhance mechanical stability (average compression strength reaches about 173 KPa). Concurrently, the hydrogel releases hydrogen sulfide (H₂S) gas, which exerts anti-inflammatory, antioxidant, pro-angiogenic, and neuroregenerative effects. Experimental data demonstrated that a 400 μL disulfide-containing hydrogel generated 28.89 ± 3.70 μM H₂S within 30 s of UV exposure. In vivo testing revealed a wound healing rate exceeding 95 % by day 14 in UV-treated hydrogel groups. The combination of these materials and their functional advantages provide a promising new way for the postoperative repair of severe scalded wounds.