Tuning surface morphology and crystallinity of anodic TiO2 nanotubes and their response to biomimetic bone growth for implant applications

Abstract

The geometry and dimensions of TiO2 nanotubes anodised under different voltages and temperatures in an organic electrolyte were manipulated to investigate the morphological, crystalline microstrcture and their response to soaking in simulated body fluid (SBF) for biomaterial implant applications. It was observed that high anodisation voltages up to 120 V increase the internal pore diameter. Hexagonally arranged nanotubes were achieved by anodisation of Ti in a lower temperature of 0 degrees C, while the geometry of nanotubes becomes circular at a higher temperature of 30 degrees C. For biomaterial application in particular the bone cell/implant biomaterial interaction, we found that the nanotubes anodised at a voltage of 120 V and a temperature of 0 degrees C exhibited a better mineralisation than those obtained under other anodising conditions. This was mainly due to the rougher and sharper tube walls which provide more suitable places for the nucleation of bio-sediments. On the other hand, annealing of the nanotubes results in the formation of crystalline sediments the amount of which was decreased compared to the as-anodised nanotubes.(C) 2017 Elsevier B.V. All rights reserved.