COMPARATIVE STUDY OF HYDROXYAPATITE PREPARED BY THE AUTHORS WITH SELECTED COMMERCIALLY AVAILABLE CERAMICS

The paper presents study of hydroxyapatites from different sources - obtained by the authors: a) Nat.HA, derived from animal bones, b) synthetic made by a wet method, - in comparison with commercial powders; Habiocer (R), and Merck (R)). All hydroxyapatites were characterized using X-ray diffraction (XRD); Fourier transformed infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM-EDS) methods. Calcium was determined by titration with EDTA (ethylenediaminetetraacetic acid) in the presence of thymolphthalein and calcein mixture whereas phosphorus was determined with the spectrophotometric method. Content of microelements was determined by the AAS and ICP method. The specific surface of the materials was measured by BET method. Volume of micro and mesopores was also determined. Synthetic hydroxyapatite, prepared by the authors by wet method was of low crystallinity, high surface area and porosity, while XRD and FT-IR characteristics were similar to commercial Merck (R). In contrast, the highest crystallinity, while the lowest surface area and porosity caused possibly by sintering of the material characterised Nat.HA (animal bone calcined at 800 degrees C). XRD and FT-IR characteristics of commercial Habiocer (R) indicated high, (similar to Nat.HA) crystallinity, however, surface area and pores were much higher than those of Nat.HA.