Abstract: A rapid and simple method for making a hydrophobically associated, Coomassie Brilliant Blue (CBB) dye/protein complex comprising CBB and a protein, and a method for detecting analytes using the CBB dye/protein complex are disclosed. The method for making the CBB dye/protein complex is comprised of mixing a protein with a non-alcoholic aqueous CBB solution having a pH greater than 4, heating the mixture to a first temperature for a short pulse period, then cooling to a second temperature to form a solution containing the CBB dye/protein complex. In the method for detecting analytes that bind a CBB dye/protein complex, the analyte sample is added to the solution containing a CBB dye/protein complex to form a supernatant and a precipitate containing an analyte-bound fraction. The precipitate is dissolved in an assay solvent, and a spectral absorption of both the precipitate and supernatant is measured.