A well designed coating for polyetheretherketone (PEEK) implants can provide enough support to overcome crucial medical challenges, which are insufficient osseointegration and high rate of infection. Herein, we utilize the co-deposition of polydopamine (PDA) and copper-citrate nanoclusters to construct a pH-responsive coating on porous PEEK for synergistic bone regeneration, vascular formation and anti-infection. Specifically, this PDA coating released high dose of copper and citrate at lower pH value, which increased intracellular copper content, boosted production of reactive oxygen species and severe damage of protein, leading to killing of 93% planktonic bacterial and eradication of adherent bacteria. At pH of 7.4, the release of copper and citrate were in a slow and sustained behavior, synergistically enhanced vascular formation potential and osteodiffereration of Ad-MSC in vitro. After implanted in rabbit tibia for 6 and 12 weeks, the micro-CT evaluation and histological analysis consistently highlighted the ability of this PDA coating to increase new bone formation adjacent to coated PEEK implant and enhance bone-implant interfacial integration. These results were proven to be related to the synergistic effect that citrate facilitated a 2-fold influx of copper into cells, which not only enhanced the bacteria-killing ability but also encouraged bone regeneration of implants. This present work provides an effective method to control infections while promoting osseointegration simultaneously, which will show tremendous clinical application and can be a solution to current challenges facing orthopedics.

设计良好的聚醚醚酮（PEEK）植入物涂层可以提供足够的支撑，以克服关键的医学挑战，即骨整合不足和感染率高。在这里，我们利用聚多巴胺（PDA）和柠檬酸铜纳米簇的共同沉积，在多孔PEEK上构建pH响应涂层，以实现骨再生，血管形成和抗感染的协同作用。具体而言，这种PDA涂层在较低的pH值下释放了高剂量的铜和柠檬酸盐，从而增加了细胞内铜的含量，增加了活性氧的产生并严重破坏了蛋白质，导致93％的浮游细菌被杀死并清除了附着细菌。在pH值为7.4时，铜和柠檬酸的释放呈缓慢而持续的行为，体外协同增强Ad-MSC的血管形成潜能和骨分化。在兔胫骨中植入6周和12周后，显微CT评估和组织学分析一致地强调了该PDA涂层能够增加与涂层PEEK植入物相邻的新骨形成并增强骨-植入物界面整合的能力。这些结果被证明与柠檬酸促进铜向细胞中的2倍流入的协同效应有关，这不仅增强了细菌的杀灭能力，而且还促进了植入物的骨再生。这项工作为控制感染同时促进骨整合提供了一种有效的方法，这将显示出巨大的临床应用价值，并且可以解决骨科目前面临的挑战。