In situ fabrication of anatase thin films with high percentage of exposed {001} facets to improve biocompatibility with MC3T3-E1 cells

Abstract

In situ anatase thin film with high percentage exposure of {001} facet was fabricated on titanium substrate via one-step hydrothermal method at low temperature from the precursor solution of (NH4)2TiF6 and HF. Nano-inverted bipyramid arrays densely covered the whole surface on as-treated Ti substrate. The structural analysis clearly indicated that as-deposited thin film only consisted of anatase TiO2 single crystal with preferred oriented {001} facets. According to the XRD patterns of as-treated anatase thin film, the integral intensity ratio of (004) to (101) peaks was as high as 7.5 which was remarkably higher than the standard value 0.18. Based on the experimental results, the growth pattern and bonding strength of nano-structural array with high percentage exposure of anatase {001} facet on Ti substrate were discussed. The biocompatibility results demonstrated that MC3T3-E1 cells grown on the as-treated Ti sheet exhibited positive effect on the cell proliferation and significantly high gene expression of ALP, COL-1, BMP-2, OPN and RUNX2 due to its specific property of the surface. Hence, the in situ anatase thin film with high percentage exposure of {001} facet was expected to achieve satisfactory primary stability for osseointegration. In situ fabrication of anatase TiO2 nano-inverted bipyramid arrays with high percentage exposure of {001} facet