Synthesis and characterization of nano-hydroxyapatite added with magnesium obtained by wet chemical precipitation

Abstract

Biogenic hydroxyapatites from mammalian bones naturally contain traces of ions, like Mg, which play a vital role in the bone remodeling process. In this way, synthetic hydroxyapatites should include this kind of mineral. In this work, hydroxyapatite added with Mg was synthesized by wet precipitation using (NH4)H2PO4, Ca(NO3)2.4H2O, and Mg(NO3)2.6H2O (0, 0.032, 0.061, and 0.123 ​M). Inductively coupled plasma and X-ray diffraction evidenced the Mg inclusion in the hydroxyapatite lattice in the same levels reported for natural hydroxyapatites. The calcination at 600 ​°C was performed to remove the reaction by-products, but it also gave rise to physicochemical changes as the coalescence and crystals recrystallization. It produced, in turn, an improvement in the crystalline quality, according to Raman analysis. Despite those physicochemical changes, all the samples remained nanometric according to scanning electron microscopy imaging.