NIR-II photo-amplified peroxidase-like activity using biocatalytic copper-based nanoplatform against subcutaneous methicillin-resistant Staphylococcus aureus infection

Methicillin-resistant Staphylococcus aureus (MRSA) has been associated with significant mortality and longer hospital stays. Artificial nanozymes not requiring antibiotics can generate enough reactive oxygen species (ROS) to kill bacteria. In this study, we synthesized hexagonal copper sulfide nanosheets (CuS NSs) using a modified one-pot synthesis. The CuS NSs demonstrated photothermal stability and superior photothermal conversion efficiency due to large surface area and existence in the second near-infrared (NIR-II) window (1270 nm), promoting the production of ROS. Upon NIR-II irradiation, CuS NSs displayed an excellent biocatalytic antibacterial role in vitro and accelerated abscess resolution, and enhanced the recovery of MRSA-infected wounds in vivo. Moreover, CuS NSs demonstrated negligible toxicity following an amplifying peroxidase-like activity through hyperthermia. Overall, CuS NSs provide a feasible strategy for using the synergistic therapeutic platform for effective therapy of deep-seated MRSA-infected wounds.