Interfacial and Defect Polarization Enhanced Microwave Noninvasive Therapy for Staphylococcus aureus-Infected Chronic Osteomyelitis

Abstract

Chronic osteomyelitis (COM), is a long-term, constant, and intractable disease mostly induced by infection from the invasion of Staphylococcus aureus (S. aureus) into bone cells. Here, we describe a highly effective microwave (MW) therapeutic strategy for S. aureus-induced COM based on the in situ growth of interfacial oxygen vacancy-rich molybdenum disulfide (MoS2)/titanium carbide (Ti3C2T x ) MXene with oxygen-deficient titanium dioxide (TiO2‑x) on Ti3C2T x (labeled as HU-MoS2/Ti3C2T x ) by producing reactive oxygen species (ROS) and heat. HU-MoS2/Ti3C2T x produced heat and ROS, which could effectively treat S. aureus-induced COM under MW irradiation. The underlying mechanism determined by density functional theory (DFT) and MW vector network analysis was that HU-MoS2/Ti3C2T x formed a high-energy local electric field under MW irradiation, consequently generating more high-energy free electrons to pass and move across the interface at a high speed and accelerate by the heterointerface, which enhanced the charge accumulation on both sides of the interface. Moreover, these charges were captured by the oxygen species adsorbed at the HU-MoS2/Ti3C2T x interface to produce ROS. MoS2 facilitated multiple reflections and scattering of electromagnetic waves as well as enhanced impedance matching. Ti3C2T x enhanced the conduction loss of electromagnetic waves, while functional groups induced dipole polarization to enhance attenuation of MW.

Magnetic Bimetallic Heterointerface Nanomissiles with Enhanced Microwave Absorption for Microwave Thermal/Dynamics Therapy of Breast Cancer

“…The initial step involves MW absorption, but not all of the electromagnetic energy is converted into thermal energy by MAMs . The MW thermal effect is mainly reflected in the second step after MW absorption, which is determined by the loss mechanism of MAMs . Therefore, the stronger dielectric loss and magnetic loss performance of MNRC will induce the more excellent MW thermal effect and then enhance the MWT.…”

“…The natural resonance and eddy current loss of Ni nanoparticles caused magnetic loss, which shifted the MA frequency to the medical frequency band, and then the heterointerface of MNRC formed by nanoengineering further induced significant interfacial polarization to increase dielectric loss, and effectively enhance the intensity of the generated MA. In addition, MNRC with strong MA performance at the medical frequency band not only improved the MW thermal effect for MWT but also promoted the production of reactive oxygen species (ROS) at the tumor site to mediate microwave dynamic therapy (MDT), achieving MDT combined with MWT for tumor inhibition. − Moreover, as a member of the platinum group metal, Ru has a variety of valence states, such as Ru 0 , Ru 3+ , and Ru 4+ , enabling MNRC to consume glutathione (GSH) and H 2 O 2 to produce O 2 in the tumor microenvironment (TME) and regulating and improving the hypoxia and high-redox properties . Finally, this MNRC-mediated microwave thermal/dynamics therapy (MTDT) effectively inhibited the development of breast cancer in the model of 4T1 tumor-bearing mice.…”

MXene‐Mediated Catalytic Redox Reactions for Biomedical Applications

“…This nanoplatform facilitated ROS generation by microwave irradiation. [89] In addition to directly transporting the sonosensitizer to the tumor site through presynthesis, Zhang et al prepared Ti 3 C 2 /CuO 2 @BSA nanocatalyst for in situ synthesis of sonosensitizer. Specifically, the acidic TME triggered the degradation of CuO 2 into Cu 2 + and H 2 O 2 .…”