Heterojunction with Photo-Responsive Therapy against Multidrug-Resistant Bacteria for Rapid Sterilization and Improved Burned Wound Healing.

Abstract

As one of the most common forms of skin injuries, skin burns are often accompanied by infection, slow tissue regeneration and severe scar formation, which significantly delay wound healing as well as affect the quality of life. Phototherapy has emerged as a promising alternative to conventional antibiotics in the treatment of infectious burn skin. However, the excessive heat generated by near-infrared (NIR) phototherapy risks causing secondary tissue damage. Herein, we develop a Ti₂C₃ MXene and copper selenide (CuSe) heterojunctions (M/C HJs) that synergistically produce high reactive oxygen species (ROS) yields and mild hyperthermia (around 50°C) under NIR irradiation while simultaneously overcoming bacterial drug resistance. In vitro antibacterial assays combined with transcriptomic analysis demonstrate that M/C HJs exert potent bactericidal effects with a sterilization rate of exceeding 99% under NIR by targeting the bacterial electron transport chain (ETC) in various pH condition. This disruption simultaneously impairs critical metabolic pathways and energy synthesis while effectively attenuating bacterial resistance mechanisms. In a murine burn infection model, M/C HJs demonstrate remarkable antimicrobial efficacy while concurrently promoting collagen deposition and suppressing hypertrophic scar formation in the wound bed. Therefore, this work opens the new mode of effective integrated treatment of burn wounds, further driving the in-depth study of clinical transformation mechanisms in the future.