Preparation of Nanohydroxyapatite by a Sol-Gel Method Using Alginic Acid as a Complexing Agent

摘要

Single-phase calcium hydroxyapatite (HAP) was synthesized by a sol-gel route using calcium nitrate solution and ammonium dihydrogen phosphate solution as Ca and P sources and alginic acid as a chelating agent. The dried gel was heat-treated at different temperatures in the range of 110°-900℃. Structural evolution from sol to gel and from the gel to HAP was studied by the powder X-ray diffraction method, Infrared spectroscopy, and thermal analyses. The formation temperature of HAP was confirmed to be ～300℃. Examination of the product obtained at 300℃ under TEM suggested the development of hexagonal-shaped nanoparticles, with the average particle size in the range of 50-100 nm.