NIR-II-enhanced Pt-MoS ₂ nanozymes for synergistic photothermal and chemodynamic therapy against methicillin-resistant <i>Staphylococcus aureus</i> to promote wound healing

Bacterial infections, inflammatory responses, and tissue hypoxia are three critical characteristics of the infection-healing process. To shorten the duration of infection and inflammation, this study developed a microenvironmental adaptive nanozyme with photothermal-enhanced multi-enzyme-like activity to address the unique challenges associated with each stage of healing. This was achieved by anchoring platinum onto molybdenum disulfide nanozymes (Pt-MoS2), which endowed them with photothermal conversion properties and biocatalytic activity. Additionally, the nanozymes generate reactive oxygen species in acidic microenvironments and consume glutathione during the early stages of infection, thus optimizing antibacterial performance. As the infection is controlled and the pH increases, the activities of oxidase-like and peroxidase-like enzymes decrease, while the catalase-like enzyme activity becomes more prominent. Pt-MoS2 mitigates the detrimental effects of excessive H₂O₂ and alleviates hypoxia through its peroxidase-like activity, thereby creating a favorable environment for wound healing. This approach has been validated in a subcutaneous abscess model infected with methicillin-resistant Staphylococcus aureus. Pt-MoS2 nanozymes present a novel strategy for subsequent anti-infective treatments.