The Impact of Mg Concentration, Microwave Irradiation Time, and Sintering on Magnesium-Hydroxyapatite Synthesis

Abstract

Hydroxyapatite synthesis is an inorganic compound that makes up the hard tissues of the human body such as bones. This study aims to substitute Magnesium (Mg) ions, which have an important role in the structure and function of the human body, in Calcium (Ca) ions from Hydroxyapatite. MgHA crystals are synthesized by mixing a solution of diammonium hydrogen phosphate and magnesium hydroxide into a calcium hydroxide solution which is then irradiated with microwaves, with variations in the concentration of Mg and irradiation time. From the XRD results show that along with the increase in Mg concentration and irradiation time the lattice parameter values a and c are reduced by 0.03 in lattice a and 0.01 in lattice c. The increase in irradiation time is proportional to the increase in crystal size (L) and crystallinity index (CI). At t = 35 it is found L = 19.08 nm and CI = 0.14. The increase in Mg concentration is proportional to the increase in crystal size and crystallinity index, the increase in Mg concentration above 0.6 M shows the presence of saturation in the binding process of Mg in the apatite structure. The sintering process at 900ºC increases the crystal size value from 19.08 nm to 52.09 nm and the crystallinity index from 0.14 to 2.97. Morphology of MgHA produces rod-shaped particles with agglomeration caused by a large amount of Mg content in apatite.