Abstract:

Due to its specific composition and microstructure, surface modification of hydroxyapatite (HA) was expected with the entry of a metal ion. In this study, HA powders were synthesized and immersed in solutions containing ions of ferrous iron. Ion exchange between Ca²⁺ and Fe²⁺ with a smaller ionic radius were characterized and investigated. This modification resulted in variation of surface charges of HA particles, frequencies of OH and PO4 stretching vibration, as well as lattice spaces of (00l) planes. Also, the chemical bond between HA powders and anionic electrolyte in solutions containing sodium oleate became weak after modification of HA surface by Fe²⁺ . The purpose of the present work is stimulating the substitution of Ca²⁺ ions in bones and teeth by ions of ferrous iron in circulatory systems of human beings.

Key words: nanomaterials; hydroxyapatite; surface modification; crystal structure