Abstract To improve cytocompatibility of Ti6Al4V alloy, porous oxide coatings were prepared on its surface through micro-arc oxidation (MAO) in the Na2B4O7 electrolyte plus KOH. The morphology and composition of the coatings were analyzed by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometer (EDS), and X-ray photoelectron spectroscopy (XPS). We found that, besides improving hydrophily, both bio-unfriendly elements of Al and V in the coatings decreased quickly when KOH was added into Na2B4O7 electrolyte from 0.05–0.35 M. While the KOH reaches 0.25 M, the values of Al and V in the coatings decreased to as low as 0.06 at.% and 0.3 at.%, respectively (compared with Ti6Al4V alloy, Al/Ti and V/Ti are reduced by 98.3% and 73.8%, respectively), which means selective removal of Al and V in MAO coatings happened. In the immersion test using simulated body fluid (SBF), the release of Al and V ions from the coatings with lower content of Al and V was much less than that of the MAO coating treated without KOH addition in the electrolyte. Cytocompatibilty tests confirm that the hierarchical oxide coatings with lower Al and V were beneficial to the adhesion, spreading, as well as the proliferation of the MC3T3 osteoblasts.

中文翻译：

---

通过从分级微弧氧化涂层中选择性去除 Al 和 V 来增强 Ti6Al4V 合金的细胞相容性

摘要 为了提高Ti6Al4V合金的细胞相容性，在Na2B4O7电解液加KOH中通过微弧氧化（MAO）在其表面制备多孔氧化物涂层。通过扫描电子显微镜 (SEM)、能量色散 X 射线光谱仪 (EDS) 和 X 射线光电子能谱 (XPS) 分析涂层的形貌和成分。我们发现，除了提高亲水性外，当 KOH 从 0.05-0.35 M 加入 Na2B4O7 电解液时，涂层中对生物不友好的 Al 和 V 元素迅速下降。当 KOH 达到 0.25 M 时，Al 和 V 的值在涂层分别降低至 0.06 at.% 和 0.3 at.%（与 Ti6Al4V 合金相比，Al/Ti 和 V/Ti 分别降低了 98.3% 和 73.8%），这意味着选择性去除 Al 和 V在 MAO 涂层中发生了。在使用模拟体液 (SBF) 的浸没试验中，Al 和 V 含量较低的涂层中 Al 和 V 离子的释放远低于电解液中未添加 KOH 处理的 MAO 涂层。细胞相容性测试证实，具有较低 Al 和 V 的分级氧化物涂层有利于 MC3T3 成骨细胞的粘附、扩散和增殖。