Production of Hydroxyapatite as an alternative formulation of bioresponsive ceramic bone replacement via wet chemistry method

Abstract

Hydroxyapatite, HAp [Ca10(PO4)6(OH2)] is a calcium-phosphate bioceramic can be produce via wet chemistry method by applying precipitation reaction. HAp bioceramic powder is synthesized as an alternative formulation of a bioresponsive ceramic bone replacement as it has good biocompability and high ability to form strong chemical bonds with human bone. Ca(NO3)2.4H2O and P2O5 were used as precursor in this reaction with stoichiometric Ca/P ratio of 1.33. The production of HAp particles were carried out by varying the process parameter such as stirring speed from 300 rpm to 700 rpm, sintering temperature from 600 ℃ to 800 ℃ and pH value of solution from 9 to 11. Overall, FTIR spectra shows that HAp consist of OH-, CO32- and PO32- functional group. Futhermore, from XRD spectra, HAp were present at 31.8 ° which is only present for the HAp powder that have been thermally treated at 600 ℃. From SEM images, HAp produced agglomerate HAp particles at range size of 7 𝜇m to 42 𝜇m. Other than characterize the chemical characteristics of HAp, the aim of this study was to investigate particle size of HAp based on different process parameter in order to produce smallest particle size for application as bone replacement. Thus, smallest particle size was produced by applying highest stirring rate of 700 rpm and pH of 11 but at sintering temperature of 800 ℃, HAp particle produced was the largest which is caused by agglomeration and particle growth.