Comments
The mixed-dye staining method of proteins in polyacrylamide gels with Eriochrome black T in combination with Rhodamine B can detect as little as 10 ng of BSA within one hour (1) and is more sensitive than Coomassie®-staining. The optimum dye concentration of Eriochrome Black T was determined to be 0.01 %. Protein bands were scanned at 560 nm by densitometer. Rhodamine B was employed at the same concentration (0.01 %). Staining solution was prepared by mixing stock solutions of Eriochrome Black T (0.02 % (w/v)) and Rhodamine B (0.02 % (w/v)) in 40 % methanol/7 % acetic acid in a ratio of 1 : 1 (v/v) just prior to use. Besides sensitivity, another advantage of the mixed-dye staining method over Coomassie® is the stability of the staining pattern after drying (60°C, 30 min; ref. 1).
Literature
(1) Jung, D.-W. et al. (1998) Anal. Biochem. 263, 118-120. Detection of Proteins in Polyacylamide Gels Using Eriochrome Black T and Rhodamine B.