A novel rotating electrochemically anodizing process to fabricate titanium oxide surface nanostructures enhancing the bioactivity of osteoblastic cells

Titanium oxide (TiO 2 ) surface layers with various surface nanostructures (nanotubes and nanowires) have been developed using an anodizing technique. The pore size and length of TiO 2 nanotubes can be tailored by changing the anodizing time and applied voltage. We developed a novel method to transform the upper part of the formed TiO 2 nanotubes into a nanowire‐like structure by rotating the titanium anode during anodizing process. The transformation of nanotubes contributed to the preferential chemical dissolution of TiO 2 on the areas with intense interface tension stress. Furthermore, we further compared the effect of various TiO 2 surface nanostructures including flat, nanotubes, and nanowires on bioactive applications. The MG‐63 osteoblastic cells cultured on the TiO 2 nanowires exhibited a polygonal shape with extending filopodia and showed highest levels of cell viability and alkaline phosphatase activity (ALP). The TiO 2 nanowire structure formed by our novel method can provide beneficial effects for MG‐63 osteoblastic cells in attachment, proliferation, and secretion of ALP on the TiO 2 surface layer. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.