The preparation and some properties of purified antibody specific for the 2,4-dinitrophenyl group.

Injection of rabbits with Freund's complete adjuvant containing bovine gamma-globulin substituted to near saturation with dinitrophenyl groups leads to the production of large amounts of antibodies specific for the 2,4-dinitrophenyl substituent. These antibodies can be isolated from sera in satisfactory yield (40 per cent) and in a high state of purity (90 per cent specifically precipitable). Hapten dissolution, which was used to screen haptens for their potential usefulness as specific reagents in the purification procedure, provides a means for evaluating, in relative terms, antibody-hapten affinities (in competition with antigen).