Shi-changxu Innovation Center for Advanced Materials, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, China.
School of Materials Science and Engineering, University of Science and Technology of China, 72 Wenhua Road, Shenyang 110016, China.
ACS Appl Mater Interfaces. 2022 May 4;14(17):19226-19240. doi: 10.1021/acsami.2c02802. Epub 2022 Apr 21.
The competition between cells integration and bacterial colonization determines the fate of implantations. To reveal the effects of clinical implant topographies on osteoblast differentiation and bacterial biofilm formation, a series of micron/submicron/nano-hierarchical structures were created at pure titanium surfaces (Ti-I, Ti-II, Ti-III). It was found that the hierarchical structures promoted MC3T3-E1 cell differentiation through contact guidance and Ti-II processed the best osteogenic ability. Undesirably, hierarchical surfaces further accelerated the biofilm formation due to submicron structures with low interaction. To reduce the risk of bacterial infections, hierarchical structures were prepared on the antibacterial Cu-bearing titanium alloy surfaces (TiCu-I, TiCu-II, TiCu-III). Hierarchical topographies not only endowed TiCu surfaces with antibacterial trapping characteristics due to CuO doped in the outermost oxides layer but also shifted the corrosion behavior of TiCu alloy into activation-passivation, increasing the Cu-ion release rate and further promoting the osteogenic differentiation. TiCu-III possessed excellent antibacterial trapping ability and optimal osteogenic action. Finally, in the osteomyelitis-modeled mice, hierarchical topographies aggravated the bacterial infection around Ti implants, which entirely lost the osseointegration, while all of the TiCu surfaces significantly inhibited the infection and accelerated the formation of new bone tunnels around the implants. studies successfully confirmed the tuning mechanism of hierarchical topographies on the biological responses of bacteria and cells to the Ti and TiCu alloys, which would pave the way to develop novel biofunctionalized metal implants.
细胞整合与细菌定植的竞争决定了植入物的命运。为了揭示临床植入物形貌对成骨细胞分化和细菌生物膜形成的影响，在纯钛表面（Ti-I、Ti-II、Ti-III）构建了一系列微米/亚微米/纳米分级结构。研究发现，分级结构通过接触导向促进 MC3T3-E1 细胞分化，Ti-II 具有最佳的成骨能力。但不理想的是，由于具有低相互作用的亚微米结构，分级表面进一步加速了生物膜的形成。为了降低细菌感染的风险，在具有抗菌作用的含铜钛合金表面（TiCu-I、TiCu-II、TiCu-III）制备了分级结构。分级形貌不仅由于掺杂在外层氧化物中的 CuO 赋予了 TiCu 表面抗菌捕获特性，而且将 TiCu 合金的腐蚀行为转变为活化-钝化，增加了 Cu 离子的释放速率，进一步促进了成骨分化。TiCu-III 具有优异的抗菌捕获能力和最佳的成骨作用。最后，在骨髓炎模型小鼠中，分级形貌加剧了 Ti 植入物周围的细菌感染，导致完全丧失骨整合，而所有 TiCu 表面均显著抑制感染并加速植入物周围新骨隧道的形成。这些研究成功证实了分级形貌对细菌和细胞对 Ti 和 TiCu 合金的生物学反应的调控机制，为开发新型生物功能化金属植入物铺平了道路。
