Dual-column determination of albumin and immunoglobulin G in serum by high-performance affinity chromatography

High-performance affinity chromatography was used for the simultaneous determination of albumin and immunoglobulin G in serum. Two columns in series, the first containing immobilized anti-albumin antibodies and the other containing protein A for binding immunoglobulin G, were eluted separately at pH 3 by means of a column-switching system. This method gave results in good agreement with commercially available methods, while requiring only 2 microliter of serum and 6.0 min per cycle. It was shown that albumin and immunoglobulin G were selectively retained, with little interference from other components, including immunoglobulins A and M.