Study On A New Type Of Nanocomposites Used To Construct Urinary Catheter Coating And Its Performance

Objectives:Catheter-associated urinary tract infections are the most common hospital-acquired infections worldwide,exacerbating problems with bacterial resistance and patient morbidity.To this end,researchers have developed many new catheters,including those containing silver,drugs,or antibiotics,but have failed to effectively reduce the incidence of catheter-associated urinary tract infections.Therefore,in order to prevent catheter-associated urinary tract infections,this study designed an effective antibacterial coating to provide a theoretical basis for later clinical application.Methods:?1?Zn?OH?₂ and palygorskite loaded with zinc element antibacterial material Pal/Zn?OH?₂ were prepared by co-precipitation method.?2?X-ray diffraction analysis,Fourier transform infrared spectroscopy,and scanning electron microscopy were used to characterize the structure and physical and chemical properties of the materials.?3?Using plasma to treat the surface of the catheter,and spraying Zn?OH?₂and Pal/Zn?OH?₂ to the surface of the medical catheter.In this way,CA@Pal/Zn?OH?₂and CA@Zn?OH?₂ were prepared.?4?In order to further verify the load of antibacterial materials,the contact angle system,scanning electron microscope,and energy spectrometer were used to characterize the catheter.?5?Antibacterial performance of the antibacterial catheter was verified through in vitro antibacterial experiments,biofilm formation experiments,and coating stability experiments.?6?The biocompatibility of the coating was verified by CCK-8 experiment and hemolysis experiment.Results:?1?The morphology and composition of the material were analyzed by X-ray diffraction analyzer,Fourier transform infrared spectroscopy and scanning electron microscope.It was found that the composite antibacterial material CA@Pal/Zn?OH?₂composed of the fiber rod crystal structure of palygorskite and the typical hexagonal flake morphology of zinc hydroxide chloride hydrate crystals.?2?The surface features and structural components of the catheter coating were analyzed by contact angle system,scanning electron microscope,and energy spectrometer.It was found that the antibacterial material was attached to the surface of the medical catheter through spray method.?3?The results of in vitro antibacterial experiments showed that the antibacterial effect of CA@Pal/Zn?OH?₂ on Staphylococcus aureus and Escherichia coli can be maintained at 100%on the 7th day.Among CA and CA@Zn?OH?₂ and CA@Pal/Zn?OH?₂,CA@Pal/Zn?OH?₂ had the best antibacterial properties.?4?The results of the biofilm formation showed that the green fluorescence on the CA@Pal/Zn?OH?₂ surface with the best antibacterial effect gradually decreases with time,and the red fluorescence gradually increases.?5?The results of environmental stability of the coatings showed that CA@Pal/Zn?OH?₂ and CA@Zn?OH?₂ can still maintain relatively good antibacterial properties after being placed in different media for 1 and 7 days.?6?The results of cell counting kit-8 assay and hemocompatibility assay indicated that CA@Pal/Zn?OH?₂ and CA@Zn?OH?₂ have good biocompatibility for both human bladder epithelial cells and human erythrocytes.Conclusions:?1?Zn?OH?₂ and palygorskite loaded with zinc ion antibacterial material Pal/Zn?OH?₂ were prepared by co-precipitation method.The spray method was then used to bond the antibacterial material to the surface of the medical catheter.?2?The prepared new antibacterial coating introduced palygorskite,thus reducing the relative addition amount of zinc element,thereby improving the biocompatibility of the material.Compared with CA and CA@Zn?OH?₂,CA@Pal/Zn?OH?₂ had better antibacterial properties.?3?Compared to CA and CA@Zn?OH?₂,CA@Pal/Zn?OH?₂had better ability to inhibit biofilm formation.?4?The hydroxyl group formed on the surface of the catheter and the silicon hydroxyl group of the palygorskite form a silicon-oxygen silicon bond.This strong chemical bond enables the antibacterial material to be stably present on the surface of the urinary catheter,so that the antibacterial coating can maintain good stability in different media.?5?In summary,the new antibacterial coating designed by this institute is expected to become a new method for controlling catheter-related urinary tract infections.