TITLE:
Role of Strontium on the Crystallization of Calcium Hydrogen Phosphate Dihydrate (CHPD)
AUTHORS:
K. Suguna, C. Sekar
KEYWORDS:
Brushite, Crystal growth, Sr additive, SEM.
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.10 No.7,
June
6,
2011
ABSTRACT: Calcium hydrogen phosphate dihydrate (CHPD, CaHPO4· 2H2O) or brushite is found quite frequently in urinary calculi (stones). Crystallization of brushite has been carried out in sodium metasilicate (SMS) gel with and without adding ‘Sr’ as additive. In pure system, dicalcium phosphate anhydrous (DCPA, CaHPO4) or monetite and hydroxyapatite (HA, Ca5(PO4)3(OH)) grew along with brushite. The presence of Sr suppressed the formation of HA and enhanced the number and size of monetite crystals and changed the morphology of brushite crystals from needle shape to octopus-like shape. The samples were characterized by powder & single crystal X-ray diffraction (XRD), scanning electron microscopy (SEM), Xray fluorescence spectroscopy (XRF), Fourier transform infrared spectroscopy (FTIR) and thermal analyses (TG-DTA).