Antibacterial activity and biocompatibility of curcumin/TiO₂ nanotube array system on Ti6Al4V bone implants

The present study addresses the issue of infection on and around titanium orthopaedic implants by modifying the Ti6Al4V implant surface with titania nanotubes via electrochemical anodisation followed by coating with a bioactive compound, curcumin. This natural phytochemical compound was used as coating material to enhance the hydrophobicity of the surface to limit initial bacterial adhesion and further to induce bacterial cell death by its biochemical action. Titanium nanotubes were coated with curcumin by direct dropping method. The study of antimicrobial activity indicates that curcumin coated nanotubular surface (TNTC) showed up to 43% and 38% reduction of <i>E. coli</i> and <i>S. aureus</i> population, respectively, within 24 h. Simultaneously, the <i>in-vitro</i> cellular experiments suggested that TNTC supported cell adhesion, proliferation and osteoblastic differentiation of mesenchymal stem cells. Thus, it was demonstrated that curcumin can serve as an effective material for coating bone plates to enhance the antimicrobial property while retaining its biocompatibility.本研究针对钛基骨科植入物及其周边的感染问题，通过电化学阳极氧化（electrochemical anodisation）法在Ti6Al4V植入物表面构筑二氧化钛纳米管（titania nanotubes）结构，随后以生物活性化合物姜黄素（curcumin）进行涂层改性。该天然植物源化学物被用作涂层材料，通过提升表面疏水性以抑制初始细菌黏附，并借助其生化作用诱导细菌死亡。本研究采用直接滴涂法将姜黄素负载于钛纳米管表面。抗菌活性实验结果显示，负载姜黄素的纳米管表面（TNTC）在24小时内可分别使大肠杆菌（E. coli）和金黄色葡萄球菌（S. aureus）的活菌数减少最高达43%与38%。与此同时，体外（in vitro）细胞实验表明，TNTC可支持间充质干细胞（mesenchymal stem cells）的黏附、增殖及成骨分化。综上，本研究证实姜黄素可作为骨科钢板的有效涂层材料，在保留生物相容性的同时显著提升其抗菌性能。