Preparation And Bioactivity Of Nano-TiO₂ Thin Film

Titanium and its alloys have been widely used as biomedical materials such as bone and dental implants due to their excellent mechanical properties and wonderful biocompatibility.But titanium itself is inert material,it needs surface modification to attain bioactivity,that is,the TiO₂thin film produced in titanium surface,then put it in simulated body fluid,hydroxyapatite can deposited on the surface.But surface bioactivity modification of titanium and its alloys is a complex process,which requires to consider the ability of bone induction,as well as the bonding strength between the thin film and the titanium substrate.In recent years,the field of interdisciplinary nanometer biological materials continuously developed,recent research suggests that compared with the micrometer scale characteristics of biological materials,nanometer scale biological materials has played a very important role in enhanced the performance on various aspects.In this thesis,TiO₂ thin films were successfully prepared on pure titanium substrate by hydrothermal method.The bioactivity was evaluated through simulated body fluid immersion.The surface morphology appearance,phase composition and wettability of modified nano-TiO₂ thin films were characterized and analyzed by using scanning electron microscopy?SEM?,X-ray diffraction?XRD?and contact angle measuring instrument.The experimental indicated that the morphology of the TiO₂huge changed with the increase of the concentration of titanium source,it changed from rod to needle shape,then to clusters.The contact angle measuring showed that all samples have small contact angle,namely super hydrophilic,which is important for bioactivity.With prolonged the time and temperature,the nanorod grow up obviously.To added different types and concentrations of surfactants to the solution have different effects on the reunite situation of titanium dioxide.After soaked in simulated body fluid 5 days,the results showed that all samples can induced the deposition of hydroxyapatite,which means excellent bioactivity.Therefore,this method of surface modification was simple,the Ti O₂ thin film was firmly adhered to titanium substrate,and with excellent bioactivity,which has a superior prospect of clinical application.