Features of the phase and the amino acid composition of human salivary stones

Study collections of salivary stones performed using X-ray diffraction techniques, IR spectroscopy and thermal analysis (Perkin Elmer SII Diamond - TG-DTA software PYRIS 7). Semi-quantitative analysis of the spectra was performed using the software Peak Fit_v 4.11 package for the detailed study of the structure of biominerals features. It demonstrated that hydroxyapatite is the major mineral component of salivary stones. According to the results of the chromatographic analysis of the quantitative content of 15 amino acids determined in the samples. Marked inhomogeneous distribution of amino acids in the composition of salivary stones, which is confirmed by the result of the cluster analysis. The hypothesis has been formulated that precursor in the formation of salivary stones of different clusters is different metastable phases: tricalcium phosphate (cluster 1) and brushite (cluster 2). Brushite was the precursor to the salivary stones of cluster 2, which defined a set of corresponding amino acid serine with a predominance. The amino acid composition with a significant predominance of glutamic acid detected for samples of cluster 1 (2-4 times higher than serine). The hypothesis was tested by means of thermodynamic and experimental modeling.