Microstructure, corrosion resistance, osteogenic activity and antibacterial capability of Mn-incorporated TiO2 coating

In the present work, a Mn-incorporated TiO2 coating has been fabricated through the facile one-step micro-arc oxidation (MAO) treatment in the electrolyte containing Na2Mn-EDTA. Microstructural characterization reveals that Mn-incorporated TiO2 coating exhibits a two-layered structure based on chemical compositions, which includes the inner layer consisting of polycrystalline TiO2 with P segregated at the grain boundary and the outer layer comprising of nano-sized Mn3O4 particles. Further, both corrosion resistance and biological performance of the Mn-incorporated TiO2 coating were investigated. It was revealed that the Mn-incorporated TiO2 coating exhibits an enhanced corrosion resistance, osteogenic activity and slightly improved antibacterial capability against S. aureus bacteria relative to that with the absence of Mn, which also exhibits negligible cytotoxicity. Hence, Mn specie is a promising candidate for the production of dual-functional biomedical surfaces for Ti implants.