Dual pH/NIR-responsive chitosan/gelatin sponge functionalized with boron nanosheets/zeolitic imidazolate framework-8/curcumin for synergistic photothermal-chemotherapy of bacteria-infected wounds.

The treatment of bacterially infected wounds requires advanced dressings capable of delivering therapeutic interventions on demand. In this study, we developed a multifunctional chitosan/gelatin (CG) sponge incorporating boron nanosheet-based nanocomposites (BZC) loaded with curcumin and zeolitic imidazolate framework-8 (ZIF-8), which acts as a pH/near-infrared (NIR) dual-responsive nanoplatform for synergistic photothermal-chemotherapy targeting of infected wounds. The CG/BZC composite sponge was fabricated by solution blending, freeze-drying and subsequent alkali-induced crosslinking, resulting in a highly porous structure that combines excellent water absorption with mechanical toughness. The boron nanosheet (B NS) core serves as an efficient photothermal agent, while curcumin (Cur) acts as a bioactive component with antibacterial and antioxidant properties. Crucially, upon exposure to near-infrared light, the B NS-mediated photothermal effect not only generates localized heat to kill bacteria but also accelerates the release of Cur by disrupting the ZIF-8 framework, thereby enabling precise, on-demand combined photothermal-chemotherapy. This synergistic strategy allows for the controlled generation of high heat at the wound site. In vivo studies using an infected wound model demonstrated that the CG/BZC sponge significantly promotes tissue regeneration and accelerates wound healing. This study provides a promising and versatile approach for designing smart responsive dressings for advanced wound care.