Photothermal Regulated Nanozyme of CuFeS Nanoparticles for Efficiently Promoting Wound Healing Infected by Multidrug Resistant Bacteria.

Peroxidase-mediated chemokinetic therapy (CDT) can effectively resist bacteria; however, factors such as the high dosage of drugs seriously limit the antibacterial effect. Herein, CuFeS nanoparticles (NPs) nanozyme antibacterial system with the photothermal effect and peroxidase-like catalytic activity are proposed as a combined antibacterial agent with biosafety, high-efficiency, and broad-spectrum antibacterial ability. In addition, the as-obtained CuFeS NPs with a low doses of Cu and Fe can change the permeability of bacterial cell membranes and break the antioxidant balance by consuming intracellular glutathione (GSH), which results in more conducive ROS production. Meanwhile, the photothermal heating can regulate the CuFeS NPs close to their optimal reaction temperature (60 °C) to release more hydroxyl radical in low concentrations of HO (100 µM). The proposed CuFeS NPs-based antibacterial system achieve more than 99% inactivation efficiency of methicillin-resistant Staphylococcus aureus (10 CFU mL MRSA), hyperspectral bacteria β-Escherichia coli (10 CFU mL ESBL) and Pseudomonas aeruginosa (10 CFU mL PA), even at low concentration (2 μg mL), which is superior to those of the conventional CuO NPs at 4 mg mL reported in the literature. In vivo experiments further confirm that CuFeS NPs can effectively treat wounds infected by MRSA and promote the wound healing. This study demonstrates that excellent antibacterial ability and good biocompatibility make CuFeS NPs a potential anti-infection nanozyme with broad application prospects.