Use of F(ab')2 antibody fragments in the synthesis of immunoadsorbents for preparing monospecific antigen.

Class specific F(ab')2 antibody fragments were prepared by pepsin digestion of the labile Fc immunoglobulin fragments in antigen--antibody precipitates. The F(ab')2 fragments were covalently coupled to cyanogen bromide-activated Sepharose 4B and the resultant immunoadsorbent used to isolate IgG from human serum with a single chromatographic step, in high yield and purity and negligible non-specific interaction. This technique affords a simple method for preparing an enriched source of class specific affinity-purified immunoglobulin antibodies suitable for many immunochemical applications.