Synthesis and characterization of arsenate/phosphate hydroxyapatite solid solution

A series of arsenate substituted hydroxyapatite was directly prepared through aqueous precipitation method. Characterization studies from elemental analysis, XRD, FT-IR spectra and SEM have confirmed the forming of the arsenate/phosphate hydroxyapatite solid solutions. The XRD analysis indicated that the unit cell a and c parameters did not vary smoothly with the degree of substitution as expected by the Vegard's Law. The solids with As/(P + As) = 0.46–1.0 were typically needle-like crystals; those with As/(P + As) = 0–0.46 large tabular. In FT-IR spectra, the area of the phosphate peak was gradually suppressed and that of the arsenate peak increased as the proportion of the arsenate increased.