Light-Activatable Ionic and Photothermal Therapy by CuAu Nanorods for Treating Wounds and Keratitis Caused by Methicillin-Resistant Staphylococcus aureus

Abstract

Bacterial infection may lead to organ damage and even death. Copper ions have attracted much attention in bacterialinfected wound treatment due to their ability to kill bacteria and promote neovascularization. However, the unsatisfied copper delivery for efficient bacteria removal and unexpected side effects due to copper accumulation in normal tissues limit its application. Here, we developed a copper−gold alloy nanorod (CuAu NR) as a photothermal agent to treat chronic wounds and keratitis with Methicillin-resistant Staphylococcus aureus (MRSA) infection. The CuAu NRs demonstrated a similar surface plasmon resonance effect as gold nanorods (Au NRs), a rod-like nanoparticle with unique plasmonic properties, and could be effectively heated up under near-infrared laser (808 nm) irradiation. The pH and temperature dual modalities-triggered copper release improved the healing effect with reduced biosafety concerns. In both MRSAinfected wounds in the mice model and MRSA-infected keratitis in the rabbit model, the CuAu NRs showed significant antibacterial activity, enhanced angiogenesis, and improved healing under laser irradiation. Together with excellent biocompatibility, our CuAu NRs can serve as a potential antibacterial material for clinical use.