Isolation of Egg Yolk Immunoglobulin-Rich Fractions Using Copper-Loaded Metal Chelate Interaction Chromatography

Abstract

Immunoglobulins were partially purified from egg yolk by metal chelate interaction chromatography (MCIC), after initial preparation of yolk with alginate precipitation. Under the phosphate-buffered equilibration conditions chosen, chicken IgG did bind to the MCIC column when small sample sizes were applied. With increasing amounts applied to the column, IgG was found to be preferentially displaced into the unbound fractions, resulting in an increase in IgG purity in the unbound. By selectively pooling the unbound fractions from a two-thirds copper-saturated 10mL MCIC column, 104mg IgG was obtained from four eggs at 75% purity. For industrial applications, the MCIC method described in the present study appears to have several advantages over current methods of yolk IgG separation.