Structural and microstructural characterization of bioapatites and synthetic hydroxyapatite using X-ray powder diffraction and Fourier transform infrared techniques

Bioapatite, the main constituent of mineralized tissue in mammalian bones and teeth, is similar in structure and composition to calcium hydroxyapatite (HAP), Ca₁₀(PO₄)₆(OH)₂. The crystallographic analyses of four bioapatites of human-, goat- and rabbit-bone and human-teeth origin, and one synthetic HAP prepared via microwave irradiation, have been carried out using X-ray powder diffraction techniques. Fourier transform infrared spectra and Rietveld analyses indicate partial replacement of PO₄^3- ions by CO₃^2- ions in all bioapatites.