Comparison of Calcium CPP, HAp and TeCP Phosphates, Obtained by Direct Reaction
In bioscience, there are several apatites constituteds by differents compositions. In the biological environment, apatites are found in bones and teeth of vertebrates with Ca/P ration from 2.0 to 0.5. It is not easy to determine the exact proportion of Ca2 + and PO43- in solution in the preparation of the process. In this study, apatites with Ca/P ration 1.0, 1.67 and 2.0 were prepared by direct reaction in an solution of H3PO4 in a suspension of Ca(OH)2, of same molarity, evalueting the crystallinity of CPP, Hap e TeCP with 1 mol/l, 3 mol/l and 5 mol/l. The samples characterized by X-ray diffraction (XRD) were compared with the standard of reference of the data base JCPDS. The composition of calcium phosphate for the differents molarity studied, resulted in a combination of phases with the exception of hydroxyapatite Ca/P ration 1.67 at concentrations 1 mol/l and 3 mol/l. But the diffractograms revealed that the increased molarity provided a decrease of some peaks of reflection of calcium phosphates with Ca/P ration 1.67. However, for the Ca/P ration 1.0 increasing the concentration, showed an increase of crystallinity of calcium phosphates. The FTIR confirmed the presence of phosphates in the spectrums around 1045 cm-1. The calcium phosphates obtained through direct reaction showed Ca/P ration is related with the technique employed, consolidating it in the preparation of these bioceramics.
Marcelo Prado and Cecília Zavaglia
S. V. de Oliveira et al., "Comparison of Calcium CPP, HAp and TeCP Phosphates, Obtained by Direct Reaction", Key Engineering Materials, Vols. 396-398, pp. 557-560, 2009