A Ca-deficient hydroxyapatite (CDHA)/MgF2 bi-layer coating with unique nano-scale topography on biodegradable high-purity Mg

Abstract Enhanced corrosion resistance and accelerated new bone formation are desired to make Mg and its alloys to be ideal candidate for bone biomaterial. For this purpose, a CDHA/MgF2 bi-layer coating was prepared on high purity Mg by a combination of fluoride treatment and hydrothermal treatment. The coating exhibited a nanoscale surface topography. Enhanced adhesion strength and corrosion resistance was obtained for the CDHA/MgF2 bi-layer coating. In vitro cell experiment showed that the adhesion, proliferation and differentiation of MG63 cells were significantly improved on Mg with CDHA/MgF2 coating compared to that on Mg with HA coating and MgF2 coating. In conclusion, this study provides a promising surface modification method for Mg metal with enhanced corrosion resistance and superior osteogenic bioactivity.