Protein G-SepharoseTM is used in affinity chromatography, protein chromatography, antibody purification and characterization, immunoaffinity matrices, protein A, G and L resins, protein interaction, and purification and detection. Protein G-SepharoseTM has been used to develop a strategy to confirm the presence of anti-erythropoietin neutralizing antibodies in human serum as well as to compare methods for depletion of albumin and IgG from equine serum.