Solution-mediated transformation of octacalcium phosphate (OCP) to apatite.

摘要: OCP crystals were hydrolyzed in solutions containing Ca2+, Mg2+, HPO4(2-), CO3(2-), F-, citrate or P2O7 ions. Products of hydrolysis analyzed using scanning (SEM) and transmission (TEM) electron microscopy, infrared spectroscopy x-ray diffraction. Results demonstrated that the to Apatite (AP) transformation is influenced by: (1) types ions solution: inhibited by P2O7(4-); facilitated HPO4(2-) Ca2+ ions; (2) ionic concentrations; (3) solution pH; (4) crystal size. SEM showed needle-like micro-crystals on surfaces ends macrocrystals. TEM side-to-side end-to-end arrangements presence central defects apatite crystals. IR spectra incorporation CO3, HPO4, HPO4 being least from F-containing solutions. These results suggest AP occurred process dissolution subsequent precipitation Ca-deficient apatites, incorporating F- present solution. indicate observed stability pathological calcifications may be due and/or P2O7(4-) low levels biological fluids.