Ni-Au Janus Nanoparticles with NIR-Amplified Cascade Catalysis for Wound Healing

Nanoscales that mimic natural cascade catalytic reactions through simple procedures, demonstrating high efficiency, have attracted extensive interest in the antibacterial field. However, the rational design of nanostructures and the improvement of their catalytic efficiency remain challenging. Herein, spindle-shaped Ni-Au Janus nanocomposites (JANs) are synthesized with asymmetric catalytic duality and NIR-responsive photothermal activation. The spatially segregated Au and Ni domains synergistically drive a catalytic cascade: the Au domain exhibits glucose oxidase-like activity to self-supply H₂O₂, while the Ni domain functions as a peroxidase to convert H₂O₂ into cytotoxic ·OH. Notably, NIR irradiation amplifies catalytic activity by promoting hot electron migration across Ni-Au heterojunctions, reducing the K_m value of H₂O₂ from 13.29 to 5.54 mm, and increasing V_max by ≈1.3-fold. Coupled with the inherent bacterial binding capacity of Ni facet, this synergistic cascade facilitates in situ ·OH production, enhancing broad-spectrum antimicrobial properties (82.75% against Escherichia coli and 83.26% against Staphylococcus aureus). The bactericidal effect is verified in vivo and maintained good cytocompatibility. These findings demonstrate that the antibacterial efficacy can be enhanced through the precise design of Janus structures and the physicochemical properties of the nanoplatform, paving the way for a novel cascade catalytic strategy in bacterial disinfection.