WET-CHEMICALLY SYNTHESIZED BETA-TRICALCIUM PHOSPHATE: EFFECT OF Ca/P MOLAR RATIO ON LOCAL STRUCTURE

抄録

Although the ripening time of wet-chemically synthesized β-tricalcium phosphate (β-TCP) influences its local structure, the effect of the Ca/P molar ratio on the local structure of β-TCP remains unclear. The main objective of the present study was to investigate the effects of the Ca/P molar ratio on the local structure of β-TCP. Single-phase β-TCP was produced by heat-treatment of precursor calcium-deficient hydroxyapatite, which was synthesized at 25 °C, pH 7.0, Ca/P molar ratio of 1.50, and a long ripening time of 72 h, whereas Ca/P molar ratios under and over 1.50 resulted in β-TCP and a HAp subphase. ³¹P MAS-NMR spectroscopy revealed that the long ripening time of 72 h led to 16 narrow-linewidth resonances from the β-TCP local structure at any Ca/P molar ratio, suggesting the specific ordering of Ca(4) sites in the β-TCP crystal structure.