Protein adsorption and wettability on fluoride treated hydroxyapatite

Abstract

We developed a new method, the Dropping Time Method (DTM), to investigate the wettability of the protein surface layer adsorbed on hydroxyapatite in aqueous solution. We then studied the relationship of the amount of adsorbed protein and wetting of the protein surface. We also investigated the adsorption of human serum albumin (HSA) on hydroxyapatite plates treated with acidulated phosphate fluoride (APF) in water. Although the surface of adsorbed HSA were fairly hydrophilic for high concentrations of HSA, the amount of protein depended on the adsorption time. At lower HSA concentrations, although the hydrophilicity of the HSA layer depeneded on the concentration of the APF, no great differences were observed in the amount of adsorbed protein. The surface of the protein layer became hydrophilic independent of the amount of adsorbed protein.