ADSORPTION BEHAVIOR OF BETA-LACTOGLOBULIN ONTO STAINLESS-STEEL SURFACES

Nonporous stainless steel particles with an average diameter of 25.5 m u m and an average surface area of 215 cm(2)/g were used to study the adsorption of beta-lactoglobulin (beta-lg), Scanning electron microsco py of stainless steel particle surfaces with adsorbed beta-lg showed a n obvious eradication of crevices as protein was adsorbed. The adsorpt ion process for beta-lg was very rapid in the first 5 min and essentia lly reached equilibrium within 10 min. Precipitation of calcium phosph ate onto the stainless steel surface war very slow compared to monolay er deposition of beta-lg. A monolayer of beta-lg adsorbed very tightly to the stainless steel surface and a significant fraction of the prot ein was irreversibly adsorbed. The amount of adsorbed protein decrease d with increasing ratio of surface area to reaction volume. pH in the range 6.0-6.8 did not significantly affect the amount of adsorbed prot ein.