Intelligent response agarose/chitosan hydrogel wound dressing: Synergistic chemotherapy, PDT and PTT effects against bacterial infection

Bacterial infections impede skin wound healing, and antibacterial hydrogels have garnered significant attention in the field of wound care due to their combined therapeutic effects. In this study, an intelligent, responsive ACGel@Cur-Au hydrogel was developed using temperature-sensitive agarose and pH-responsive chitosan as the structural framework, infused with Gel@Cur and AuNR. The AC-Gel@Cur-Au hydrogels demonstrated excellent mechanical properties, swelling capacity, tissue adhesion, and biodegradability. Upon irradiation, the hydrogels exhibited effective photodynamic therapy (PDT), photothermal therapy (PTT), and heat-sensitive gel-sol conversion capabilities, allowing for the release of curcumin in response to temperature and pH changes. Through these synergistic effects, the AC-Gel@Cur-Au hydrogel displayed a rapid bactericidal effect against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), effectively treating persistent biofilms. In vivo studies using a full-thickness defect model of S. aureus infection demonstrated that the hydrogel possessed strong antibacterial activity and enhanced wound healing capabilities, significantly reducing inflammation. Furthermore, the hydrogel significantly promoted granulation tissue formation, collagen deposition, and angiogenesis. Importantly, all the components of the AC-Gel@Cur-Au hydrogel were found to be non-cytotoxic, indicating good biocompatibility. This safe, synergistic antibacterial hydrogel holds great promise for the treatment of bacterial infections in wound healing.