High-sensitivity electrophoretic method for the detection of Bence Jones protein and for the study of proteinuria in unconcentrated urines.

The study of proteinuria, and especially the search for Bence Jones proteins (BJP), has almost always required urine concentration. We evaluated a high-sensitivity electrophoretic method using unconcentrated urine based on colloidal gold staining. The sensitivity for the detection of BJP is further enhanced by immunofixation. Sensitivity to BJP is better than 1 mg/L and, apart from the alpha-1 microglobulin, all the proteins relevant to the classification of proteinuria can be visualized with a sensitivity of approximatively 3 mg/L.