Chitin-Assisted Synthesis of CuS Composite Sponge for Bacterial Capture and Near-Infrared-Promoted Healing of Infected Diabetic Wounds.

Diabetic wounds are prone to recurrent infections, often leading to delayed healing. To address this challenge, we developed a chitin-copper sulfide (CuS@CH) composite sponge, which combines bacterial trapping with near-infrared (NIR) activated phototherapy for treating infected diabetic wounds. CuS nanoparticles were synthesized and incorporated within the sponge using a chitin assisted biomineralization strategy. The positively charged chitin surface effectively adhered bacteria, while NIR irradiation of CuS generated reactive oxygen species (ROS) heat and Cu to rapidly damage the trapped bacteria. This synergistic effect resulted in an exceptional antibacterial performance against (∼99.9%) and (∼99.3%). The bactericidal mechanism involved NIR-induced glutathione oxidation, membrane lipid peroxidation, and increased membrane permeability. In diabetic mouse models, the CuS@CH sponge accelerated the wound healing of infected wounds by facilitating collagen deposition and reducing inflammation. Furthermore, the sponge demonstrated good biocompatibility. This dual-functional platform integrating bacterial capture and NIR-triggered phototherapy shows promise as an antibacterial wound dressing to promote healing of infected diabetic wound.