ADSORPTION OF HUMAN-SERUM ALBUMIN ON PRECIPITATED HYDROXYAPATITE

The adsorption of human serum albumin on precipitated stoichiometric hydroxyapatite Ca10(PO4)6(OH)2, /CaHA/ was followed in a wide pH range. Adsorption was irreversible toward dilution; the isotherms were not of the Langmuir type, but of a stepwise nature. The amount of HSA adsorbed was found to be dependent on the pH and the ionic strength. It decreased with increasing pH, thus indicating the effect of charge repulsion. This effect could be counteracted by increasing the ionic strength, i.e., the concentration of the neutral electrolyte, potassium nitrate. Partial desorption could be effected by increasing the pH of the solution. Adsorption of human serum albumin decreased with increasing temperature. © 1979.