Solid state synthesis of calcium borohydroxyapatite

Calcium borohydroxyapatite was synthesized by the solid-state reaction of colemanite (Ca2B6O11 center dot 5H(2)O) and diamonium hydrogenphosphate ((NH4)(2)HPO4) at 1200 degrees C for 12 h. X-ray diffraction pattern showed only the formation of calcium borohydroxyapatite. The experimental analysis assigned the chemical formula as Cal(10)[(PO4)(5.80)(BO3)(0.20)](OH)(2). It was indexed in the hexagonal system with the refined unit cell parameters of a = 9.557(3) angstrom, c = 6.926(8) angstrom and space group P6(3)/m. The experimental results verified that if colemanite was used as a primary reactant for both calcium and boron source, the calcium borohydroxyapatite could be obtained. (C) 2011 Elsevier Masson SAS. All rights reserved.