Magnesium-incorporated sol-gel Ta2O5 coating on Ti6Al4V and in vitro biocompatibility

Tantalum (Ta) has been used to modify the surface of titanium (Ti) due to its superior biological response under some clinically compromised situations such as osteoporosis and diabetes; however, the techniques used presented technical disadvantages. The currently study prepared Ta2O5 and Mg-incorporated Ta2O5 coatings on Ti6Al4V by a sol-gel method and compared in vitro response of rabbit bone marrow mesenchymal stem cells. Both coatings were submicrometer-thick and comprised nano-sized particles, the former being crystalline whereas the latter amorphous. Compared with uncoated Ti6Al4V, both coatings increased the corrosion resistance and water wettability, and improved the viability, proliferation, osteoblastic differentiation of the cells. Moreover, they also upregulated the expression of an angiogenesis-related gene (HIF-1α). With the exception of corrosion rate, greatest improvements were observed from the Mg-incorporated Ta2O5 coating. These improvements were probably due to the nanostructures and elements release of Mg and Ta from the coatings. All above results suggest that, Ta2O5-based coatings are promising tools for improving the biological response of Ti-based implants under compromised conditions.