Study On Microwave Response Of Copper-Cerium Based Bimetallic Oxide Antibacterial Material

Osteomyelitis,caused by bacterial infection,results in increased bone fragility and the ability of the bacteria to cause inflammation elsewhere through the blood in the bone marrow,which in severe cases can lead to lifelong disability and life-threatening conditions.In clinical practice,high doses of antibiotics are often used for treatment.However,this can lead to the development of bacterial resistance.Therefore,it is necessary to propose new strategies to improve the efficacy of treatment based on the specific problems of osteomyelitis.To reduce the possibility of bacterial resistance,we can use exogenous triggers such as light,ultrasound,and microwaves to assist in the treatment of therapeutic materials.However,osteomyelitis occurs within the bone marrow cavity,and the limited penetration of light limits therapeutic efficacy.Microwaves and ultrasound are highly penetrating and have great potential in treating osteomyelitis in deep tissue infections.Cerium dioxide is the most important and representative cerium oxide.The mixed valence state possessed by the cerium ion,which catalyzes the production of ROS,enables antimicrobial properties to be achieved.The introduction of additional components such as noble or non-precious metal oxides on top of Ce O₂enables better catalytic properties to be achieved.Furthermore,the appropriate doping of metal ions in the cerium oxide lattice can improve its catalytic properties,resulting in a multi-component hybrid structure with better catalytic properties than the corresponding single-component structure.In this paper,CuCeO_x was successfully prepared by adjusting the ratio of copper and cerium salts prior to hydrothermal treatment,after hydrothermal treatment followed by calcination,and the successful introduction of the copper source was confirmed by understanding its basic characterization and morphology through some tests pairs such as scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,Raman spectroscopy（Raman）,fluorescence spectroscopy（PL）,etc.In addition,the antimicrobial treatment in vitro by microwave-enhanced Fenton-like therapy and the treatment of bacterial infectious osteomyelitis by microwave synergy were carried out.Furthermore,the biosafety of the material was evaluated.The research in this paper can be divided into three parts:1.Mechanism of microwave remote response to CuCeO_xCuCeO_xwas successfully prepared by adjusting the ratio of copper and cerium salts before hydrothermal treatment,after hydrothermal treatment followed by calcination.The successful introduction of the copper source was confirmed by some test pairs to understand its basic characterization and morphology.The enhanced mechanism of microwave catalytic performance of CuCeO_x materials was analyzed by exploring the microwave thermal properties,dielectric properties,microwave electrochemistry,and microwave kinetics to generate reactive oxygen species.Probably due to the non-thermal effect of microwaves and the effect of microwave radiation material dielectric properties,will be in the formation of abundant hot spots,accelerated as well as the vibration and friction of polar molecules in the system,so that electromagnetic energy is converted into thermal energy,the local electric field and heat stimulated by the emergence of free electrons and holes,conducive to the conversion of adsorbed oxygen species to active oxygen species.2.CuCeO_x for in vitro antimicrobial therapy via microwave-enhanced Fenton-like therapyWhen CuCeO_x is irradiated by microwaves,it can produce bacteria in the surrounding environment to be attacked by ROS produced by CuCeO_x,while the temperature increases so that the bacteria become sensitive to heat.The combination of the thermal effect of MW with its own electric field increases the permeability of the bacterial membrane,allowing copper ions to easily pass through the bacterial membrane and react with the H₂O₂ inside the bacteria in a Fenton-like reaction.Subsequently,the bacteria continue to be disrupted,resulting in damage to the bacterial membrane and protein leakage.Microwave heat,ROS,and the released copper ions,as well as the accelerated consumption of glutathione,eventually led to bacterial death.CuCeO_x showed excellent antibacterial activity against S.aureus and E.coli under microwave treatment.3.Validation of CuCeO_x synergistic microwave therapy for bacterial infectious osteomyelitis and biosafetyThe long-term copper ion release behavior was studied to obtain concentrations of released copper ions well below the toxicity limit.According to the MTT results,it was shown that microwave irradiation leads to large amounts of copper ions,and the negative effects caused by incubation over a long period of time fade away.The observation of the cell morphology also demonstrates that the material has good cytocompatibility.The safety of the blood was demonstrated by measuring the hemolysis rate.Also,the in vivo antimicrobial effect was demonstrated by blood tests,tibial H&E,and Giemsa staining charts.Finally,the absence of organ damage caused by the material was demonstrated by H&E plots of vital organs.Microwave synergy with copper-cerium bimetallic oxide is a promising approach to treating bacterially infected osteomyelitis and can effectively eliminate osteomyelitis and other deep-seated infections caused by bacteria.