Chemical Characterization of a Potassium Hydroxyapatite Prepared by Soaking in Potassium Chloride and Carbonate Solutions

Article type: Research Article

Authors: Nordström, E. G. | Karlsson, K. H.

Affiliations: Department of Chemical Engineering, Abo Akademi University, SF-20500 Abo, Finland

Abstract: A potassium-doped synthetic apatite was prepared by soaking hydroxyapatite in potassium carbonate and potassium chloride solutions. The hydroxyapatite was prepared by firing slip cast ceramic bodies in vacuum at 1100°C. The conical ceramic samples and a crushed material of this were soaked in carbonate and chloride solutions for 2, 4, 6, and 8 weeks. Potassium, calcium, and phosphate were determined by direct current plasma emission spectroscopy. The carbonate content was determined by thermogravimetric analysis and chloride titrimetrically. After 2 weeks, one potassium ion substituted one calcium ion when soaked in a carbonate solution. When soaked in the chloride solution substitution occurred to the same extent. At phosphate sites the substitution of phosphate for carbonate occurred at one sixth of the sites after 2 weeks. Chloride incorporated one half of the OH-sites after 2 weeks. After 4 weeks about one chloride ion was found in the apatite, and after 6 weeks one and a half of the OH-sites were occupied by chloride ions.

Keywords: hydroxyapatite, potassium, doped

DOI: 10.3233/BME-1992-2402

Journal: Bio-Medical Materials and Engineering, vol. 2, no. 4, pp. 185-189, 1992