Preparation and Properties of Copper-Substituted Hydroxyapatite Powders and Ceramics

Abstract

Abstract—Hydroxyapatite powders containing up to 2.4 mol % Cu (Cu-HA) have been synthesized via precipitation from solution. The synthesized materials have been characterized by X-ray diffraction after heat treatment in the temperature range from 900 to 1400°C and their lattice parameters and crystallite size have been determined. We have studied the bending strength and microstructure of Cu-HA-based ceramics. The results demonstrate that the addition of more than 0.8 mol % copper reduces the thermal stability of HA, leading to its partial decomposition to monoclinic tricalcium phosphate (α-TCP) and its transformation into the hexagonal phase (β-TCP), with possible concentration of the copper in it. Increasing the percentage of copper leads to a decrease in HA sintering rate in combination with an increase in crystallite size and porosity. According to in vitro biological investigations, the ceramic materials are cytocompatible and their surface has marked matrix properties.