仿生多尺度表面构筑与生物润滑机制研究

The replacement joints is ofen in the poor lubrication condition. Wear particles generated from the process of insufficient lubrication in human body especially for the polymer is a major cause for the failure of artificial joints, which lead to osteolysis and aseptic loosening. The cartilage as a bearing material has the porous structure. Meanwhile, the superficial zone of cartilage is thought to contain charged macromolecules—proteoglycans, which are glycosolated and bound to hyaluronic acid to form a brush-like layer. This layer plays an important role in water absorption and improves the lubrication properties of articular cartilage. It has been suggested that similar synthetic brushes on artificial joint may also lead to low friction. Therefore, in order to prolong the service life of artificial joints and ensure a successful artificial joint replacement, it is necessary to modify the artificial joint by mimicking the surface characteristics of natural cartilage. Based on the hydrodynamic lubrication theory, the porous array texture on the artificial joint bearing surface was prepared and then zwitterionic electrolyte brushes were grafted on the surface of texture. The bionic multiscale structure surface is constructed. Combining the fluid hydrodynamic lubrication of microporous texture, the hydration layer lubrication of polar polymer brush, the super lubrication and super wear resistant are achieved. The biocompatibility is also improved at the same time. The effects of interaction of lubrication components and grafted electrolyte brush with lubrication components on the lubrication behavior will be investigated. At the same time, the synergism effects of lubrication components with grafted electrolyte brush will be studied. The molecular lubrication mechanism is also be Researched. Also, the biocompatibility of bionic multiscale surface is studied. The wear test is carried out using the joint simulator. The study would provide the theoretical and technical support for the application of the bionic surface in artificial joint and other implants.

置换关节常处在不良润滑状态，润滑不足产生的大量磨屑是导致人工关节无菌松动和晚期失效的主要因素。本研究模仿天然关节软骨表层多孔和浅表层滑膜腔电解质刷的结构与润滑功能，基于流体润滑理论在关节承载表面制备多孔阵列织构，在织构表面接枝两性离子电解质刷，构筑具有自愈合功能的仿生多尺度结构表面。利用微孔织构产生的流体动压润滑、极性刷产生水合层润滑和生物电解质润滑组分在接枝电解质刷表面形成的自组装膜润滑的协同作用，实现超润滑和耐磨功能，同时也改善生物相容性。研究滑液与接枝电解质刷之间的相互作用对润滑行为的影响和它们的润滑协同效应，研究分子润滑机理。研究仿生多尺度表面的生物相容性。研究仿生多尺度表面的生物摩擦学行为与配副关系。在关节模拟器上进行试验考核。为仿生表面在人工关节等植入物上的应用奠定基础。

置换关节常处在不良润滑状态，润滑不足产生的大量磨屑是导致人工关节无菌松动和晚期失效的主要因素。天然关节软骨不含血管，损伤后几乎没有自修复能力，但其使用寿命平均达70年之久，远高于目前人工关节的使用寿命（10-15年），与其超润滑能力密切相关。本研究模仿天然关节软骨表层多孔和浅表层滑膜腔电解质刷的结构与润滑功能，分别以UHMWPE、钛合金及PEEK等为人工关节摩擦副，在其表面构筑多孔与接枝聚合物刷仿生结构，利用微孔的流体动压润滑与聚合物刷水合层润滑的协同效应，实现了接近天然关节软骨的润滑性能，摩擦系数低于0.03，并保持了长期稳定性，同时显著提高了耐磨性。为实现具有天然关节的缓冲减振、超润滑及耐磨功能的新型仿生人工关节的设计、制备提供了理论基础和技术支撑。项目期间申请发明专利14件，其中获发明授权3件；发表SCI论文22篇；编著出版《生物材料与组织工程》1本；获江苏省科学技术（自然）三等奖1项；培养博士毕业研究生6名，硕士毕业研究生5名。