Simple purification of goat IgG1 and IgG2 subclasses by chromatography on protein A-sepharose at various pH

Abstract

Two ml of goat serum are applied on a 2 × 20 cm column of protein A-Sepharose at pH 9.1. Elution at the same pH yields two protein peaks, the second being highly purified IgG1. A minor Ig fraction, eluted at pH 6.5, is discarded. Pure IgG2 is then eluted at pH 5.9. Yields of both subclasses average 70 %.