Clinical analysis of human serum proteins using the Beckman automated Paragon 2000 CZE system.

Abstract

Electrophoretic separation and quantitation of serum proteins, including paraproteins, remain essential for the diagnosis and management of a variety of disorders. We examined the Beckman automated Paragon 2000 capillary zone electrophoresis (CZE) system and compared its electropherograms to those obtained by cellulose acetate electrophoresis (CAE). Within-run CVs using seven different capillaries and between-day CVs for CZE were <2% for albumin; they were <6% for α1-globulin, α2-globulin, β-globulin, and γ-globulin. From 2.7 to 15.0g/dl of total protein concentrations, the same electrophoretic patterns could be observed. Comparisons of the five principal bands obtained by CZE and cellulose acetate electrophoresis (CAE) gave correlation coefficients from 0.8 to 0.9. On a quantitative basis in 55 specimens, albumin by CZE was on average 10% lower than CAE, and α1-globulin and β-globulin were 93% and 15% higher than by CAE, respectively (p<0.001). Based on our use of the Beckman Paragon software and our reference values (percent of total protein) for CZE of 56.3 to 68.9% for albumin, 3.9 to 6.3% for α1-globulin, 4.8 to 8.4% for α2-globulin, 7.9 to 11.9% for β-globulin, and 9.9 to 21.5% for γ-globulin, we found 75% to 100% agreement with CZE; i.e., both methods gave either normal or abnormal results of the time. Patients showing a gammopathy gave values that were higher by CZE 60% of the time. Furthermore, the CZE system can resolve prealbumin, α1-acid glycoprotein, α1-antitrypsin, hemopexin, transferrin, and complement besides to the usual five bands.