ROS-Modulating Bio-Heterojunction Nanosheets for Infected Wound Healing via Nanozyme Activity.

Reactive oxygen species (ROS) play a pivotal role in wound healing due to their ability to eradicate bacterial infections. However, excessive ROS can induce oxidative stress and prolonged inflammation, which significantly hinder the wound-healing process. To address this challenge, Ti3C2Tx-Se NPs (TS) heterojunction nanosheets, are developed which enhance electron transfer under near-infrared (NIR) laser irradiation confirmed by ultraviolet photoelectron spectroscopy (UPS) analysis. Compared to Ti3C2Tx, TS exhibits superior antibacterial activity against S. aureus and E. coli through the synergistic mechanisms of chemical dynamic therapy (CDT) and photothermal therapy (PTT). In the absence of laser treatment, TS demonstrates a "ROS modulating effect", effectively scavenging ROS through catalase (CAT) and superoxide dismutase (SOD) activities. TS efficiently eliminated hydroxyl radicals (90.87%), superoxide anion (76.33%), and hydrogen peroxide (95.72%) at low concentration, thereby minimizing oxidative damage. In vivo studies further reveal that TS significantly reduces oxidative damage, clears bacterial infections, and promotes angiogenesis, thereby accelerating wound healing. TS offers precise ROS regulation while leveraging the synergistic effects of PTT and CDT. This material not only exhibits potent antibacterial properties but also alleviates excessive ROS accumulation, mitigates inflammation, and fosters tissue regeneration, making it a promising candidate for the treatment of infectious wounds.