Single-Atom-Catalyzed MXene-Based nanoplatform with Photo-Enhanced Peroxidase-Like activity nanotherapeutics for Staphylococcus aureus infection

Deep-seated possess the stubbornness and deep penetration of the infection into the tissue, which was a significant challenge to rapid eradication for healing. Nanozyme technology has potential applications in infection treatment due to its non-antibiotic dependence, topical, and non-invasiveness. MXene-loaded single-atom (SA) catalysts have attracted increasing attention, and SAs hybridized on titanium vacancies of MXene are forecasted to have excellent catalytic properties. However, their catalytic properties have not yet been used for anti-infective therapy. Herein, we synthesized titanium carbide MXene (Ti3C2)-based on hybridizing Pt single-atom (Pt-Ti3C2). The Pt SA exhibit the desired peroxidase (POD)-like activity to locally catalyze hydrogen peroxide and generate hydroxyl radicals, which effectively kill bacteria and remove biofilms. Moreover, Pt-Ti3C2 demonstrates ultrahigh photothermal conversion efficiency under NIR irradiation at low concentrations (40 μg/mL). The temperature increase caused by the photothermal effect of Pt-Ti3C2 significantly amplifies the POD-like activity. Theoretical calculations revealed that the Pt single atoms regulate the photothermal and POD-like properties of Pt-Ti3C2 by changing the band gap, charges, and atomic dispersion. Finally, a satisfactory photothermally-amplified nanozyme catalysis strategy was applied to rapidly eliminate bacteria in deep-seated infection and accelerate abscess resolution with ignorable side effects. This work provides an effective therapeutic strategy for photothermally amplified bio-catalyzed anti-infection therapy based on single-atom catalysis and MXenes.