[Fabrication of titanium dioxide nanotube array and effects of its osteoblast proliferation and alkaline phosphatase activity].

Objective: To investigate preparation parameters of TiO2 nanotube layer with anodization, and to evaluate the osteoblast activity on TiO2 nanotube layer in vitro.

Methods: Titanium dioxide nanotube layer was grown using anodization method. TiO2 nanotube layers with different structure were obtained by controlling the voltage and time of anodization and rinsing process after anodization. Pure titanium without anodization was used as control. Osteoblasts were cultivated on the anodizated TiO2 nanotube, and the growth of osteoblasts was then evaluated and analyzed.

Results: The voltage, duration of anodization and rinsing process following anodization were key factors to affect morphology of TiO2 nanotube layer. The area of osteoblast cultured on TiO2 nanotube layer was larger than that on pure titanium. Results from methylthiazol tetrazolium (MTT) test showed that the proliferation of osteoblasts after 96 h cultivation on TiO2 nanotube layer (0.62 +/- 0.02) was significantly higher than that on unanodizated titanium (0.55 +/- 0.03, P < 0.05). Three weeks later, the alkaline phosphatase (ALP) activity on TiO2 nanotube layer [(130.8 +/- 5.1) A(405)/mg] was significantly higher than that on unanodizated titanium [(109.6 +/- 4.5) A(405)/mg, P < 0.05].

Conclusions: The structure of TiO2 nanotube layer was greatly associated with anodization voltage. The TiO2 nanotube layer had a positive effect on osteoblast behavior.