具有体内磨损自修复功能的碳基薄膜及其在人工器官摩擦配副表面改性中的应用

In order to reduce the wear and metal ion release of artificial organs, such as joint prosthesis, artificial intervertebral discs, and to enhance the stability of diamond-like carbon film on these artificial organs in vivo, carbon based films doped with metal atom (Me-DLC) will be fabricated on the friction component. In this project the interaction of metal ion and protein and the formation mechanism of biofilm and graphite layer on friction interface will be firstly studied. Then Me-DLC films with different doped metal and dose will be fabricated and these Me-DLC films with different doped metal and dose will have different surface physical and chemical properties. Metal ion will released during Me-DLC wear in vivo, the catalysis of metal ion and the special physical and chemical properties of the Me-DLC film surface will regulate and control the formation of biofilm and graphite layer. The compact biolfilm and graphite layer can be as a protective layer induced by the wear self-repairing function of Me-DLC. The compact biofilm and graphite layer can prevent corrosion medium into the interface of Me-DLC and substrate through the micropores of Me-DLC. As the wear continues, the biofilm and graphite layer will be both wear off and then the fresh Me-DLC will be exposed in body fluid again. The metal ion, which is released during Me-DLC wear, will stimulate the adsorption, denaturation, degradation of protein and also will promote the formation of biofilm and graphite layer. During Me-DLC service in vivo, the compact biofilm and graphite layer will formed and break down again and again, which is resulted from the wear self-repairing function of Me-DLC and the abrasion. The biofilm and graphite layer will continuously restrain the corrosion of the interface of Me-DLC and substrate. And this will enhance the stability of Me-DLC film on artificial organs in vivo.

为了减轻关节、人工椎间盘等人工器官摩擦配副表面磨损及金属离子的释放，提高摩擦配副表面类金刚石薄膜在体内服役的长期稳定性，本项目在研究金属离子-蛋白相互作用、摩擦表面生物薄膜及石墨层形成机制的基础上，设计制备碳基薄膜（掺金属的类金刚石薄膜，Me-DLC）。生理环境下Me-DLC磨损释放金属离子，利用金属离子的催化作用及薄膜表面性质调控摩擦表面生物薄膜、石墨层的形成，生物薄膜及石墨层实现对Me-DLC的修复（Me-DLC磨损自修复过程），阻止腐蚀介质通过Me-DLC的孔隙进入薄膜/基体界面，抑制界面腐蚀；随着磨损的进行，生物薄膜、石墨层磨损完成，裸露出Me-DLC，再次利用Me-DLC磨损释放出金属离子促进Me-DLC表面蛋白吸附、变性、分解及生物薄膜、石墨层的形成，在不断的摩擦过程中，通过生物薄膜及石墨层对碳基薄膜的修复，抑制了界面腐蚀，提高了人工器官摩擦副表面Me-DLC薄膜的长期稳定性。

为了减轻关节、人工椎间盘等人工器官摩擦配副表面磨损及金属离子的释放，本项目在关节、人工椎间盘表面制备具有磨损自修复功能的薄膜材料，提高关节及人工椎间盘耐磨性，减少并发症的发生。项目首先研究金属离子对薄膜表面蛋白吸附、变性及分解的影响，研究了摩擦条件下金属离子对摩擦配副表面生物薄膜及石墨层形成的影响；进一步设计制备掺金属Cu和Ag的类金刚石薄膜（Me-DLC）及氮化钛薄膜（Cu-TiN），研究摩擦配副表面石墨层的形成及磨损自修复性能，生理环境下薄膜磨损释放金属离子，利用金属离子的催化作用及摩擦力促进摩擦界面生物薄膜、石墨层的形成，实现对薄膜的修复（磨损自修复过程）；随着磨损的进行，生物薄膜、石墨层磨损完成，裸露出新的薄膜材料，再次利用薄膜材料磨损释放出金属离子促进摩擦界面蛋白吸附、变性、分解及生物薄膜、石墨层的形成，在不断的摩擦过程中，通过生物薄膜及石墨层对薄膜的修复，提高了薄膜表面改性人工器官摩擦副的耐磨性，降低并发症的发生；本项目最后研究了具有自修复功能的碳基薄膜（Me-DLC）及Cu-TiN薄膜的生物安全性。项目揭示金属离子及摩擦条件对摩擦配副表面生物薄膜、石墨层形成的影响机制，探讨了在模拟生理环境下TiCuN薄膜及掺金属类金刚石薄膜表面生物薄膜及石墨润滑层的形成机制，优化设计、制备出具有自修复功能碳基薄膜（Me-DLC）及TiCuN薄膜。本项目为发展出具有自主知识产权、耐磨性高、长寿命新型人工关节、人工椎间盘置换产品奠定基础，有助于提高人工关节、人工椎间盘的质量。