A rapid chromatographic technique for the detection of dye-binding proteins

A rapid and inexpensive assay for dye-binding proteins has been developed. It depends on the separation of free and protein-bound sulfobromophthalein in 1-ml columns of Sephadex G-25 due to differential adsorption of the dye to the protein and to the Sephadex. With bovine serum albumin the calibration curve is linear between 0.03 and 3 mg of protein and is not affected by the presence of moderate concentrations of salt.