Estimation of serum proteins by electrophoresis on cellulose acetate.

We have evaluated results for albumin obtained by a standard procedure for cellulose acetate electrophoresis of proteins in serum. The Ponceau S-stained .albumin and globulins were eluted and the albumin was calculated by the generally accepted formula [(albumin-bound dye absorbance/absorbance of total protein-bound dye) X total serum protein concn] and by the formula (absorbance of albumin-bound dye in test/absorbance of albumin-bound dye in a reference serum) X concn of albumin in reference serum. The ratio of values by the first and second methods ranged from 0.93 to 1.30, the first giving the higher results in cases of discrepancy. These findings confirm the limitations in accurately calculating any serum-protein fraction by the first method. The second method appears to be the more accurate.