Magnetic Composite Rapidly Treats Staphylococcus aureus-Infected Osteomyelitis through Microwave Strengthened Thermal Effects and Reactive Oxygen Species.

It is difficult to effectively treat bacterial osteomyelitis using photothermal therapy or photodynamic therapy due to poor penetration of light. Here, a microwave (MW)-excited magnetic composite of molybdenum disulfide (MoS 2 ) / iron oxide (Fe 3 O 4 ) is reported for the treatment of bacteria-infected osteomyelitis. In in vitro and in vivo experiments, MoS 2 /Fe 3 O 4 is shown to effectively eradicate bacteria-infected mouse tibia osteomyelitis, due to MW thermal enhancement and reactive oxygen species (ROS) ( 1 O 2 and ·O 2 - ) production under MW radiation. In addition, the mechanism of MW heat generation is proposed by MW network vector analysis. By the density functional theory and finite element method, the ROS generation mechanism is proposed. The synergy or conductive network between dielectric MoS 2 and magnetic Fe 3 O 4 can reach both enhancement of the dielectric and magnetic attenuation capability. In addition, abundant interfaces are generated to enhance the attenuation of electromagnetic waves by MoS 2 and Fe 3 O 4, introducing multiple reflections and interfacial polarization. Therefore, MoS 2 /Fe 3 O 4 has excellent MW absorption ability based on the synergy or conductive network between MoS 2 and magnetic Fe 3 O 4 as well as multiple dielectric reflections and interfacial polarization.