Single-Atom Catalysis for Efficient Sonodynamic Therapy of Methicillin-Resistant Staphylococcus aureus-Infected Osteomyelitis.

Osteomyelitis, as a severe bone disease caused by bacterial infection, can result in lifelong disability or fatal sepsis. Considering that the infection is stubborn and deep-sited in bone tissue, in situ and rapid treatments for osteomyelitis remain a significant challenge. Herein, we prepare an ultrasound (US)-activated single-atom catalyst that consists of a Au nanorod (NRs)-actuated single-atom-doped porphyrin metal-organic framework (HNTM-Pt@Au) and red cell membrane (RBC), which can efficiently treat methicillin-resistant Staphylococcus aureus (MRSA)-infected osteomyelitis under US. Besides the outstanding performance in the field of photocatalysis, we find that single atoms (such as Pt, Au, Cu) also improve the sonocatalytic ability of the sonosensitizer. Due to the strong electron-trapping and oxygen adsorption capacity, the Pt single atom endows RBC-HNTM-Pt@Au with an excellent sonocatalytic activity. It shows an excellent antibacterial performance with an antibacterial efficiency of 99.9% toward MRSA under 15 min of US irradiation. Meanwhile, the RBC-HNTM-Pt@Au can be propelled directionally under US and thus dynamically neutralize the secreted toxins. The MRSA-infected osteomyelitis in rat tibia was successfully treated, which shows negligible bone loss, reduced inflammation response, and great biocompatibility. This work presents an efficient sonodynamic therapy for the treatment of deep tissue infections via a multifunctional single-atom catalyst.