The first report of the use of the "G" form of the dye to visualise protein bands in polyacrylamide gels came in 1967, where the dye was dissolved in an acetic acid solution containing methanol.[12] It was subsequently discovered that the protein bands could be stained without staining the polyacrylamide by using a colloid of the "G" form of the dye in a trichloroacetic acid solution containing no methanol. Using this procedure it was no longer necessary to destain the gel.[13] Modern formulations typically use a colloid of the "G" form of dye in a solution containing phosphoric acid, ethanol (or methanol) and ammonium sulfate (or aluminium sulfate).[14][15][16][17]