High bone-like apatite-forming ability of mesoporous titania films

In vitro bioactivity of Ti alloy can be enhanced by mesoporous titania films (MTFs), which were prepared on Ti6Al4V substrates by evaporation-induced self-assembly (EISA) process. In vitro bioactivity tests of the MTFs were studied by immersing them in simulated body fluid (SBF). The effect of the mesostructure on improving the apatite-forming ability of the MTFs was investigated through XRD, SEM, TEM and FTIR. The MTFs showed a mesoporous anatase structure with large surface area, high pore volume, and a narrow pore size distribution. Calcium-deficient hydroxycarbonate apatites were observed after soaking the MTFs in SBF for 7 days, rather than 14 days for conventional titania films (TFs). These demonstrated that the mesostructure greatly improved the bioactivity of the MTFs, which was attributed to high specific surface area, suitable pore size and high pore volume. The induced apatite by the MTFs was very similar to bone-like apatite, including Mg, Na ions, carbonated structure and ordered nano-network structure. In this work, the MG63 cell proliferation experiment indicated that the MTFs had a good biocompatibility and can provide surface suitable for the MG63 cell proliferation. Such MTFs on Ti alloys have potential application in implanting and bone regeneration materials in the future.