ESTIMATION OF SERUM PROTEINS BY QUANTITATIVE DENSITOMETRY AFTER GEL ELECTROPHORESIS.

The problem of obtaining quantitative results from polyacrylamide gels was approached by modifying a commercially available densitometer designed for paper electrophoresis. The light beam was collimated into a thin sheet which passed through the diameter of the cylinder of gel as the latter was advanced continuously. The recorded densitometric trace was integrated manually and the fractional areas of albumin, transferrin, and macroglobulin bands were studied for reproducibility. Replicate analyses of various steps were performed and duplicate runs of five serum samples were made. The standard deviation of the overall procedure for each of the three fractions studied was 5-10 of the measured levels. It was concluded that, used with care, the technique can provide valuable qualitative information as well as quantitative data. Author