Composite Nanoarchitectonics of Nanozymes with Cascade Enzyme Activity Enable Controlled Regulation of Reactive Oxygen Species for Bacterial Infection-Induced Wound Healing

Bacterial infections severely impede the healing process of infected wounds, and the key challenge to achieving efficient healing of infected wounds lies in precisely regulating the generation and clearance of reactive oxygen species (ROS) across spatiotemporal scales. However, traditional nanozymes struggle to dynamically adapt to fluctuating ROS demands at different stages within the microenvironment. To address this, we designed and synthesized the GO-FePPOP TFP nanocomposite, which promotes wound healing by dynamically regulating ROS levels through synergistic multienzyme cascade reactions, photodynamic therapy, and photothermal therapy. This composite exhibits outstanding photothermal properties and exceptional photodynamic therapeutic effects, significantly impairing bacterial antioxidant defense capabilities. Furthermore, GO-FePPOP TFP enables dynamic ROS regulation via near-infrared (NIR) switching. Under NIR irradiation, it exhibits enhanced oxidase-like activity, generating abundant ROS and demonstrating outstanding antibacterial performance. Upon cessation of NIR irradiation, GO-FePPOP TFP exerts superoxide dismutase-like and catalase-like activities, effectively scavenging residual ROS and alleviating inflammatory responses. Consequently, the cascade self-cyclic enzyme activity system based on GO-FePPOP TFP coordinates ROS dynamic equilibrium and modulates the inflammatory microenvironment at the wound site, significantly promoting wound healing. This work overcomes the limitation of single-therapy approaches prone to inducing drug resistance, offering important insights for developing highly effective antimicrobial materials to treat infected wounds.