Study On Surface Modification Of Biomedical Titanium And Its Antibacterial Activity And Bioactivity

Titanium and titanium alloys are the most popular implant materials for medical use because of their excellent properties.It has excellent mechanical properties and good biocompatibility,but no good antimicrobial properties.If the surface of biomedical materials,especially implanted materials titanium and titanium alloy,can realize physical and chemical antibacterial,and form a surface with special functional structure and composition on the surface,it is of great significance to inhibit and prevent bacterial adhesion and transfer through a physical passive contact killing way.It will be of great clinical value to construct nanocolumn or nanocolumn with special morphology on the surface of titanium and titanium alloy implants,regulate the composition of the surface at the same time,make the surface interface functionalized,and realize the antimicrobial properties without drug resistance.The philosophy of this paper is through the way of hydrothermal treatment in the structure on the surface of titanium alloy titanium dioxide nano structure,then the first step by heat treatment,forming stable fixed nanometer column template,then sodium the acid soaking replacement,after the second step heat treatment to achieve the transformation of TiO2 crystal type,formed a stronger stability,corrosion resistance and wear resistance better surface of titanium dioxide,finally by ion immersion and supersonic elution,hydrophilic and completely removing impurity of pure titanium oxide nano structure,implement physical antibacterial.On the other hand,we load very small amount of nano-silver antibacterial substances on its structure to achieve synergistic antibacterial so as to improve its antibacterial performance without cytotoxicity..The main research contents and conclusions of this paper are as follows:(1)Using sodium hydroxide as the hydrothermal reaction medium,the titanium substrate was hydrotreated.Through orthogonal test and single factor variable experiment,the effects of different process conditions.The alkali concentration,hydrothermal time,temperature,etc.in the surface morphology were investigated.The titanium dioxide nanocolumn structure was constructed on the surface of titanium.The surface morphology,elemental composition,phase composition,3D structure,hydrophilicity and hydrophobicity of the modified sample were analyzed by SEM,XRD,XPS,AFM and contact angle testers.The antibacterial activity and cytotoxicity of the modified sample was evaluated by antibacterial and cytotoxicity tests.The modified samples have high antibacterial properties and no potential cytotoxicity.(2)Ag-TiO2 nanoparticles loaded with silver were prepared on the surface of titanium alloy samples after hydrothermal treatment by the method of reducing silver nitrate by ultraviolet light.The reduction of silver nitrate solution with different concentrations was studied,and the loading amount of silver decreased with the decrease of the concentration of silver nitrate solution.EDS element analysis and antibacterial test were carried out,and it was finally found that the antibacterial rate of Ag-TiO2 sample was as high as 99%when 0.0005 M AgNO3 solution was used for preparation,the content of Ag in the sample was the lowest,and there was no potential cytotoxic effect.