Synthesis and characterization of nanosized magnesium-doped fluorapatite powder and coating for biomedical application

Abstract

Nanosized hydroxyapatite (HA) powders exhibit a greater surface area and are expected to have better bioactivity than coarser crystals. In addition, properties of HA can be tailored over a wide range by incorporating different ions into HA lattice. In this study nanosized magnesium-doped fluorapatite powders with different magnesium content are prepared by sol–gel method and calcinated at different temperatures. Moreover, magnesium-doped fluorapatite coatings are applied on 316L stainless steel substrates by sol–gel dip coating method. Results confirmed the incorporation of magnesium and fluoride ions into HA lattice. Increasing calcination temperature not only alters the crystallinity and crystallite size, but also affects the phase composition of obtained powders. The crystallite size and crystallinity of obtained nanopowders were in the range of 40–70 nm and 75–85 %, respectively. Magnesium-doped fluorapatite coating obtained after 24 h aging and one time dip coating was thinner in thickness and morphologically was more homogeneous and had less cracks. Since the obtained magnesium-doped fluorapatite has structural properties similar to biological apatite, they are expected to be appropriate candidates for bone substitution materials and body implants.