BACKGROUND:Titanium implants are widely used in clinical practice because of their high strength and good biocompatibility.However,during implantation,bacterial infection and tissue damage environment produce a large number of reactive oxygen species,which can easily lead to delayed tissue healing and surgical failure.Consequently,the development of titanium implants with antimicrobial and antioxidant properties becomes paramount. OBJECTIVE:Considering the potent antimicrobial attributes of copper ions and the remarkable antioxidant qualities of polyphenols,we proposed the fabrication of polyphenol-mediated copper ion coatings on titanium surfaces.These coatings were subsequently assessed for their in vitro antimicrobial and antioxidant properties. METHODS:Nanostructures were generated on the titanium surface using the alkali thermal method.The titanium was immersed in a solution containing tannic acid and copper ions to achieve polyphenol-mediated copper ion coatings.The surface morphology and water contact angle were detected.The loading and release of copper ions were examined using atomic absorption spectroscopy.Staphylococcus aureus was inoculated on the surface of pure titanium sheet(blank group),alkali heat treated titanium sheet(control group),and polyphenol mediated copper ion modified titanium sheet(experimental group)to observe the bacterial survival status.Osteoblast precursor cells MC3T3-E1 were co-cultivated on the surface of three groups of titanium sheets to assess their antioxidant properties and bioactivity. RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the polyphenol-mediated copper ion modified titanium sheet had rod-like nanostructures and no cracks on the surface.The surface hydrophilicity of copper ion modified titanium sheet mediated by polyphenol was close to that of pure titanium sheet.Atomic absorption spectrometry results showed a 51%increase in the loading capacity of copper ions after polyphenol mediation,with a uniform release of copper ions.(2)The antibacterial rates of titanium sheets in the blank group,control group,and experimental group were 0%,21.65%,and 93.75%,respectively.The live/dead staining and CTC staining showed that the live bacteria on the surface of titanium plates in the blank group were the most,and the live bacteria on the surface of titanium plates in the experimental group were the least.(3)The results of live/dead staining and CCK-8 assay showed that the three groups of titanium sheets had good cytocompatibility,and the titanium sheets in the experimental group were more conducive to the proliferation of MC3T3-E1 cells.Active oxygen fluorescence probe detection exhibited that compared with the other two groups,the fluorescence intensity of active oxygen on the surface of the experimental group was significantly reduced.The results of alkaline phosphatase and alizarin red S staining showed that the osteogenic differentiation and extracellular matrix mineralization of MC3T3-E1 cells on the surface of titanium sheets in the experimental group were stronger than those in the other two groups.(4)These results show that the polyphenol-mediated copper ion coating has strong antibacterial and antioxidant properties and promotes osteogenic differentiation.