Effect of chemical treatments on the ionic conductivity of carbonate apatite

A poorly crystallized carbonate-apatite analogous to bone mineral is prepar ed by co-precipitation at room temperature and dried by lyophilisation. The effect of different media (CO32-, HPO42-,OH- and F-) on its ionic conducti vity properties is investigated. Infra-red spectroscopy and chemical analys is were used to characterize the treated and untreated apatites. Frequency- dependent ionic conductivity was rapidly attenuated succeeding F- treatment or accentuated following CO32- treatment. These results were explained by the occurrence of structural order or disorder in back of F- or CO32- chemi cal treatments, respectively. Electrical studies using complex impedance 3 method show that HPO42- groups contribute to the Conductivity of these biom aterials. (C) 2001 Elsevier Science Ltd. All rights reserved.