Detection limits for protein after electrophoresis on cellulose acetate.

The detection limits for protein, when stained with nigrosine after electrophoresis on cellulose acetate, was studied and shown to be: albumin, 3-0 ng; transferrin, 0.8 ng; and Bence-Jones protein, 0.8 ng. This was less than one-hundredth of the previously reported levels. Immunofixation, although useful for identification, did not lower the detection limit for Bence-Jones protein.