Surface modification of titanium implants with micro–nano-topography and NIR photothermal property for treating bacterial infection and promoting osseointegration

A double acid corrosion and subsequent hydrothermal treatment were used to fabricate a micro–nano-structured Ti substrates (Ti–M–N). Afterward, the mesoporous polydopamine (MPDA) nanoparticles as photothermal agent were prepared and immobilized on the surface of Ti–M–N samples, in order to obtain Ti–M–N-MPDA sample. Unique micro–nanostructure properties and the photothermal effect of the modified Ti implant caused physical stress on the bacteria and the bacterial membrane damage, and eventually led to bacteria death. More importantly, based on excellent bioactivity and cytocompatibility of mussel-inspired materials, MPDA promoted adhesion, proliferation and osteogenic differentiation of mesenchymal stem cells in vitro. Furthermore, animal experiments in vivo further confirmed that the modified Ti implants could enhance osseointegration. 使用双酸腐蚀和随后的水热处理来制造微纳米结构的 Ti 衬底 (Ti-M-N)。 随后, 制备了作为光热剂的介孔聚多巴胺 (MPDA) 纳米颗粒并将其固定在 Ti-M-N 样品的表面, 以获得 Ti-M-N-MPDA 样品。 独特的微纳米结构特性和改性钛植入物的光热效应对细菌造成物理压力和细菌膜损伤, 最终导致细菌死亡。 更重要的是, 基于贻贝材料优异的生物活性和细胞相容性, MPDA在体外促进间充质干细胞的粘附、增殖和成骨分化。 此外, 体内动物实验进一步证实, 改性钛植入物可以增强骨整合