The Formation of Calcium and Magnesium Phosphates of the Renal Stones Depending on the Composition of the Crystallization Medium
- 95 Downloads
The study of the phase formation of phosphates in the solutions simulating the normal inorganic composition of human urine was carried out by the precipitation method. All calcium and magnesium phosphates typical for the kidney stones were synthesized: brushite, octacalcium phosphate, hydroxyapatite, struvite and Mg-whitlockite. The regularities of the calcium and magnesium phosphates formation in the crystallization medium of variable composition were found out. The borders of the crystallization areas of the synthesized phases were determined in the axes «initial pH value—main components’ concentration». In general, phosphates crystallization areas are defined by the starting concentrations of the main components, pH value of the crystallization medium and by the presence of the additional ions in the solution. It was shown that crystallization of any calcium phosphate leads to the significant decreasing of the pH value of the crystallization medium. Adding of the inorganic components typical for the human urine into the Ca–PO4 system leads to the moving of the crystallization area borders of the calcium phosphates (brushite, octacalcium phosphate, apatite). Crystallization doesn’t occur in the areas that are characterized by the composition and pH typical for the normal human urine. Increasing amount of the precursors or pH values leads to the start of the phosphate crystallization.
KeywordsBiominerals Pathogenic crystallization Phase equilibrium Precipitation method Renal stones Apatite Brushite Struvite Octacalcium phosphate Whitlockite
This work was supported by President of Russian Federation grant for leading scientific schools (No. NSh-3079.2018.5) and Russian Foundation for Basic Research (№19-55-45019 IND_a). The instrumental investigations have been performed at the Research Resource Centers of St. Petersburg State University: Centre for X-ray Diffraction Studies, Centre of Microscopy and Microanalysis, Nanotechnologies Centre. The authors are deeply grateful to Yu. O. Punin, Professor at the Department of Crystallography at St. Petersburg State University, who proposed and organized this experimental study of crystallization in phosphate systems that simulate the normal composition of human urine with respect to the inorganic components.
- Borodin EA (1991) Biochemical diagnoisis. Part II. Blagovesthensk: 77 (in Russian)Google Scholar
- Chhiber N, Sharma M, Kaur T, Singla SK (2014) Mineralization in health and mechanism of kidney stone formation. Int J Pharm Sci Invention 3(10):25–31Google Scholar
- Fisang C, Anding R, Muller SC, Latz S, Laube N (2015) Urolithiasis—an interdisciplinary diagnostic, therapeutic and secondary preventive challenge. Dtsch Arztebl Int 112:83–91Google Scholar
- Furedi-Milhofer H (2010) Physiological and pathological mineralization: some problems and possible solutions. Med Vjesn 42(3–4):33–44Google Scholar
- O’Kell AL, Lovett AC, Canales BK, Gower LB, Khan SR (2018) Development of a two-stage model system to investigate the mineralization mechanisms involved in idiopathic stone formation: stage 2 in vivo studies of stone growth on biomimetic Randall’s plaque. Urolithiasis. https://doi.org/10.1007/s00240-018-1079-1CrossRefGoogle Scholar
- Zhang S (2013) Hydroxyapatite coatings for biomedical applications. CRC Press, Boca Raton, London, New York, p 463Google Scholar