AFFINITY OF MOUSE IMMUNOGLOBULIN-G SUBCLASSES FOR SIALIC-ACID DERIVATIVES IMMOBILIZED ON DEXTRAN-COATED SUPPORTS

High-performance liquid affinity chromatography is a powerful method f or the purification of biological compounds owing to its specificity, rapidity and high resolution. In our laboratory, we develop chromatogr aphic supports based on porous silica beads. However, in order to mini mize non-specific interactions between the inorganic surface and prote ins in aqueous solution, the silica beads are coated with modified dex tran. As previously reported, many affinity ligands can be covalently grafted onto dextran-coated silica. In this study, N-acetylneuramic ac id, which belongs to the sialic acid family and is present in immunogl obulin G (IgG) epitopes, is used as an active ligand. The interactions of this affinity support and IgG subclasses are analyzed. This immobi lized ligand enables purification of IgG3 antibodies.