Incorporation of carbonate and magnesium ions into synthetic hydroxyapatite: The effect on physicochemical properties

Hydroxyapatite (HA), magnesium containing hydroxyapatite (Mg-HA) and magnesium containing carbonated apatite (Mg-CHA) were prepared by the wet chemical synthesis. Various analytical methods, such as X-ray diffraction (XRD), infrared spectroscopy (FTIR) and high-resolution solid-state nuclear magnetic resonance (SSNMR) were applied to characterize physicochemical properties of the studied samples. The synthesized apatites were found nanocrystalline with the absence of additional phases. Mg-CHA was less crystalline than the other samples and presented the highest specific surface area. The material had chemical composition and morphological features similar to that of bone mineral. Chemical differences between crystal surface and crystal interior of the analyzed samples (i.e. Mg2+, CO32-, HPO42- and water distribution) were discussed.