The IgG fc fragment does not bind antigen; however, it does contain the classic antigenic determinants and biological activity with respect to cytotrophic reactions, binding of complement and catabolic rate control. No reaction by IEP to antisera to human IgG-fab. Prepared from plasma shown to be non reactive for HbsAG, anti-HCV, anti-HBc, and negative for anti-HIV 1 & 2 by FDA approved tests. >95percent pure by SDS-PAGE.