Solid-state NMR and IR characterization of commercial xenogeneic biomaterials used as bone substitutes

Three commercial xenogeneic biomaterials (Gen-Os, Apatos Spongiosa and Apatos Cortical; all from Tecnoss Dental, Torino, Italy) originated from porcine bone were characterized by various analytical methods, such as powder X-ray diffraction (XRD), thermogravimetry (TGA), high-resolution solid-state nuclear magnetic resonance (ssNMR) and infrared spectroscopy (FT-IR). The studies were focused on structural properties and chemical compositions of the samples. It was found that the main constituents of the analyzed biomaterials were nanocrystalline apatite mineral, organic collagenous matrix and water. For comparison, synthetic carbonated hydroxyapatite and natural collagen type I from bovine tendon were used. Differences in various physicochemical parameters such as crystal size, specific surface area, concentration of structural hydroxyl groups, contents of CO32− and HPO42− ions and their location were discussed. It was shown that various techniques of ssNMR and elaborate analysis of the FT-IR spectra, applied together, provide valuable information on xenogeneic biomaterials.