COMPARISON OF ADSORPTION BEHAVIOR OF BOVINE SERUM ALBUMIN AND OSTEOPONTIN ON HYDROXYAPATITE AND ALUMINA

Abstract

Adsorption behavior of bovine serum albumin (BSA) and osteopontin (OPN) on osteoconductive hydroxyapatite (HA) and non-osteoconductive alpha-type alumina (-Al2O3) was studied as function of protein concentration and pH, using Bradford dye binding assay. BSA showed a much larger binding capacity on -Al2O3 than that on HA irrespective of BSA solution concentration and pH. Furthermore, OPN is likely to show the same adsorption characteristic as BSA. Definite correlation was not observed between the albumin or OPN adsorption capacity and the osteoconductivity of materials, suggesting that other factors (e.g., orientation, arrangement, etc. of albumin and/or OPN) likely govern expression of the osteoconductivity. (Received February 2, 2012; Accepted March 30, 2012)