Interface Polarization Strengthened Microwave Catalysis of MoS2/FeS/Rhein for the Therapy of Bacteria-Infected Osteomyelitis

Staphylococcus aureus (S. aureus)-induced osteomyelitis is fatal to patients, even leading to death without timely debridement processing, which is difficult to be treated by antibiotics or phototherapy due to deep infections. Herein, a microwave (MW) assisted bacteria-killing strategy for treating S. aureus-induced osteomyelitis by using MW-responsive molybdenum disulfide (MoS2)/ferrous sulfide (FeS) heterojunction with anti-inflammatory herb of rhein (Rhe) is reported. Under medical MW irradiation, MoS2/FeS/Rhe effectively eradicates S. aureus-infected rat tibial osteomyelitis. The robust therapeutic effects of MoS2/FeS/Rhe are ascribed to the anti-inflammatory effect of Rhe, the enhanced MW thermal and dynamic effects of MoS2/FeS. MoS2/FeS is composed of S-Mo-S-Fe-S stacked layers sandwiched in between by weak Van Der Waals interactions, which means that ions or molecules can be retained in the space between the layers. Under MW irradiation, dipoles or ions are aligned in an oscillating electric field, which cause dipolar polarization and ionic conduction, leading to molecular friction and dielectric loss to generate MW heat. In addition, the dipole orientation polarization caused by the interfacial polarization of MoS2/FeS is the main factor for microwave catalysis. This kind of MW responsive nanocomposite comprising inorganics and herbs may solve the challenge of how to effectively treat deep tissue infections.