Qin Liguo, Sun Hongjiang, Hafezi Mahshid, Zhang Yali
Key Laboratory of Education Ministry for Modern design & Rotary-Bearing system, Xi'an Jiaotong University, Xianning west road, Xi'an 710049, China.
Institute of design science and Basic component, Xi'an Jiaotong University, Xianning west road, Xi'an 710049, China.
Materials (Basel). 2019 Sep 17;12(18):3014. doi: 10.3390/ma12183014.
Due to their bioinert and reliable tribological performance, cobalt chromium molybdenum (CoCrMo) alloys have been widely used for articular joint implant applications. However, friction and wear issues are still the main reasons for the failure of implants. As a result, the improvement of the tribological properties and biocompatibility of these alloys is still needed. Thus, surface modification is of great interest for implant manufacturers and for clinical applications. In this study, a strategy combining laser surface texturing and chitosan grafting (mussel inspired) was used to improve the tribological and biocompatible behaviors of CoCrMo. The microstructure and chemical composition were investigated by atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy, respectively. The tribological properties were discussed to determine their synergistic effects. To evaluate their biocompatibility, osteoblast cells were cocultured with the modified surface. The results show that there is a distinct synergistic effect between laser surface texturing and polymer brushes for improving tribological behaviors and biocompatibility. The prepared chitosan brushes on a textured surface are a strong mechanism for reducing friction force. The dimples took part in the hydrodynamic lubrication and acted as the container for replenishing the consumed lubricants. These brushes also promote the formation of a local lubricating film. The wear resistance of the chitosan brushes was immensely improved. Further, the worn process was observed, and the mechanism of destruction was demonstrated. Co-culturing with osteoblast cells showed that the texture and grafting have potential applications in enhancing the differentiation and orientation of osteoblast cells.
由于其生物惰性和可靠的摩擦学性能，钴铬钼（CoCrMo）合金已被广泛用于关节植入应用。然而，摩擦和磨损问题仍然是植入物失效的主要原因。因此，仍需要改善这些合金的摩擦学性能和生物相容性。因此，表面改性对植入物制造商和临床应用具有极大的吸引力。在本研究中，采用激光表面纹理化和壳聚糖接枝（受贻贝启发）相结合的策略来改善CoCrMo的摩擦学和生物相容性。分别通过原子力显微镜、扫描电子显微镜和X射线光电子能谱研究了微观结构和化学成分。讨论了摩擦学性能以确定它们的协同效应。为了评估它们的生物相容性，将成骨细胞与改性表面共培养。结果表明，激光表面纹理化和聚合物刷之间在改善摩擦学行为和生物相容性方面存在明显的协同效应。在纹理化表面上制备的壳聚糖刷是降低摩擦力的有力机制。凹坑参与了流体动力润滑，并充当补充消耗润滑剂的容器。这些刷还促进了局部润滑膜的形成。壳聚糖刷的耐磨性得到极大提高。此外，观察了磨损过程，并展示了破坏机制。与成骨细胞共培养表明，纹理化和接枝在增强成骨细胞的分化和取向方面具有潜在应用。
