Enhancement of corrosion resistance and bioactivity of titanium by Au nanoparticle-loaded TiO2 nanotube layer

To further improve the modified benefit of TiO2 nanotube (TN) arrays as an implant surface layer, Au nanoparticles (AuNPs) were uniformly loaded into TN arrays by using a simple electrochemical deposition method. Morphology, phase composition, surface roughness, and water contact angle of as-prepared AuNP-TN arrays were examined through various characterizations. AuNP-TN arrays exhibited much rougher surface and higher surface energy than pure Ti and TN arrays without loading of AuNPs. The corrosion behavior in simulated body fluids was evaluated by a potentiodynamic polarization test, and the corrosion resistance of the AuNP-TN arrays was significantly enhanced. In vitro bioactivity assessments showed that the AuNP-TN arrays possessed higher apatite-forming ability than pure Ti and TN arrays. In vitro cell culture tests also confirmed that the AuNP-TN array surface could promote osteoblast cell attachment and proliferation. The highly active surface of AuNP-TN arrays was believed to provide a solid and practical foundation of effective substrate for implant designs.