Structural, Morphological, and Resorption Properties of Carbonate Hydroxyapatite Prepared in the Presence of Glycine

Abstract

Carbonate-containing hydroxyapatite has been synthesized from prototype human synovial fluid in the presence of glycine. The resultant powders have been shown to contain 75 to 80 wt % the amino acid. If the model solution contains less than 0.08 mol/L of glycine, the latter influences neither the composition of the solid phase nor the size of the forming crystallites, but changes the degree of their crystallinity and the specific surface area of the material. At high amino acid concentrations, we observe the formation of poorly crystallized composites consisting of smaller nanocrystallites. The dissolution of the samples in a 0.9% NaCl solution has been shown to be a two-step process. The highest solubility under weakly acidic conditions has been demonstrated by the precipitates containing the largest amount of the amino acid.