Coomassie^® Brilliant Blue G 250 is a triphenylmethane dye used in protein gel electrophoresis for detection of proteins and with the Bradford method to determine protein concentration. G 250 is differentiated from the R 250 Coomassie stain by the addition of two methyl groups and the slightly greenish tint to its blue color. The dye may exist as a cation (red form) at a pH below 0 with an absorbance peak at 470 nm, an anion (blue form) at a pH above 2 with an absorbance peak at 595 nm, and a neutral, green form at a pH around 1 with an absorbance peak around 650 nm. The blue, anionic form is what binds with amino acid residues, such as arginine or aromatics, to form a stable complex. Corresponds to SERVA Blue G (cat. no. 35050).

λmax. (0.001 %, pH 7) A 1 cm/λmax./1 % pH 7

585 ± 5 nm ca. 500

Coomassie = registered trademark of ICI Ltd.


EINECS: 228-058-4 • WGK: 2L • HS: 32041200
Storage Temperature: +15 °C to +30 °C