Conformation of adsorbed gamma-globulin and beta-lactoglobulin. Effect of surface concentration.

The conformation of both adsorbed gamma-globulin and beta-lactoglobulin is dependent on surface concentration. Infrared bound fraction measurements show that the fraction of adsorbed carbonyl groups decreases as the amount adsorbed increases, while the ellipsometrically measured extension is higher for adsorption from higher concentration solutions. Similar studies with a cross-linked gamma-globulin preparation indicate that the native conformation in solution corresponds to an adsorbed conformation intermediate between those found at the extremes of high and low surface concentration.