Sodium inhibits the formation of ammonium-substituted solid solutions of octacalcium phosphate by filling its substitution site

摘要: Octacalcium phosphate (OCP) is a layered type of calcium that shows promise for pharmaceutical and biomedical applications because it offers both excellent biocompatibility unique, robust crystal structure readily accepts substitution by various molecules. Although several cations can be incorporated into the OCP lattice ionic substitution, little known about relative probability different ions to substitute lattice. In this study, we focus on Na NH4, which are enter substitution. We investigate these two most likely in system containing ions. work, fabricated from monocalcium monohydrate via hydrolysis solution 1 mol L−1 (NH4)2HPO4 with NaCl concentrations ranging 0 100 mmol L−1. X-ray diffraction thermal analyses indicate characteristic NH4 attenuated as concentration increases. Furthermore, when exceeds 50 (Na/NH4 ≥ 1/20), almost completely disappears. These results more ionically substituted than thereby inhibits structural change caused NH4.