The influence of the hydroxyapatite synthesis method on the electrochemical, surface and adsorption properties of hydroxyapatite

Hydroxyapatite is a compound that belongs to the group of apatite minerals. It is a very interesting adsorbent and the main inorganic component of bones and teeth. Hydroxyapatite was obtained using three different methods. The samples were designated as HAP1, HAP2 and HAP3. The synthesized adsorbents were characterized by the following methods: thermal analysis, EDAX, XRD, FTIR, adsorption and desorption of nitrogen. The electrochemical properties were studied by electrochemical titration and zeta potential. The protein used was bovine serum albumin; its concentration was 5 mg/ml. The adsorbed protein concentration was determined based on the absorbance measurements at lambda = 279 nm by UV-VIS. The characteristics are pHpzc = 6.64, 6.22, 6.43 at the HAP1/NaCl, HAP2/NaCl, HAP3/NaCl interfaces respectively and the pHiep values are about 4 for all the systems. The thermal stability of hydroxyapatite changed due to the bovine serum albumin adsorption. Synthesis method of hydroxyapatite influences on electrochemical properties and adsorption of bovine serum albumin on it.