Enhanced cellular osteogenic differentiation on Zn-containing bioglass incorporated TiO2 nanorod films

Surface nanotopography and bioactive ions have been considered to play critical roles on the interactions of biomaterials with cells. In this study, a TiO2 nanorod film incorporated with Zn-containing bioactive glass (TiO2/Zn-BG) was prepared on tantalum substrate, trying to evaluate the synergistic effects of nanotopograpgy and bioactive ions to promote cellular osteogenic differentiation activity. The expression of osteogenic-related genes, ALP as well as the ECM mineralization on TiO2/Zn-BG film were significantly upregulated compared to that of the film without TiO2 nanorod nanostructure (Zn-BG) or without Zn (TiO2/BG). Moreover, a much low Zn2+ release level on TiO2/Zn-BG film was beneficial to promote the osteogenesis, which could be ascribed to that a semi-closed space established by TiO2 nanorods with adhered cells provided an appropriate micro-environment that facilitated Zn2+ adsorption.