医用金属表面溶胶-凝胶法和离子束合成TiO_2薄膜的结构、性能比较

Comparison of Structure and Properties of TiO_2 Films Synthesized by Sol-Gel and Ion beam on Biomedical NiTi Alloy

采用溶胶-凝胶法和离子束增强沉积法在医用NiTi合金表面制备TiO2薄膜以提高其生物相容性.利用X射线衍射（XRD）、原子力显微镜（AFM）和X光电子能谱（XPS）对薄膜的结构、表面形貌及组成进行了比较研究;电化学腐蚀实验表明,两种方法制备的TiO2薄膜对金属基体均起到一种保护膜的作用,能够提高医用金属材料在模拟体液中的抗腐蚀性;对薄膜表面固定肝素抗凝血分子进行研究发现,溶胶-凝胶法制备的TiO2薄膜表面能够获得较好的肝素固定效果.

In order to improve the biocompatibility of NiTi alloy, TiO2 films were synthesized on the surface by sol-gel and Ion beam enhanced deposition (IBED) methods, respectively. The structure, surface morphology and composition of the films were studied comparatively by X-ray diffraction (XRD), atomic force microscopy (AFM) and X-ray photoelectron spectra (XPS). The electrochemical corrosion measurement shows that the two kinds of TiO2 films both can improve the corrosion resistance of metallic biomaterials in simulated body fluid as a protective layer on the surface. In order to further improve the anticoagulation of implants, immobilization of heparin molecule on the film surface was also investigated. The results indicate that sol-gel-derived TiO2 film can obtain better heparin immobilization effects than Ion beam derived TiO2 film.