Coomassie brilliant blue is the name of two similar triphenylmethane dyes that were developed for use in the textile industry but are now commonly used for staining proteins in analytical biochemistry.

[2] In 1896 during the Fourth Anglo–Ashanti War, British forces had occupied the town of Coomassie (modern-day Kumasi in Ghana).

The blue disulfonated triphenylmethane dyes were first produced in 1913 by Max Weiler, who was based in Elberfeld, Germany.

The dye molecules bind to proteins, including those in wool (keratin), to form a protein–dye complex.

[8] This is the basis of the Bradford assay, which quantifies protein by Coomassie brilliant blue dye binding.

Coomassie brilliant blue R-250 was first used to visualise proteins in 1963 by Fazekas de St. Groth and colleagues.

The sheet was then soaked in sulfosalicylic acid to fix the protein bands and transferred to a solution of the dye.

[11] Two years later in 1965 Meyer and Lambert used Coomassie brilliant blue R-250 to stain protein samples after electrophoretic separation in a polyacrylamide gel.

[12] Subsequent publications reported that polyacrylamide gels could be successfully destained using an acetic acid solution.

[15][16][17][18] The Bradford assay uses the spectral properties of Coomassie brilliant blue G-250 to estimate the amount of protein in a solution.

The dye is noted for its high level of sensitivity: 5 μg of protein[clarification needed] can be detected.

In 2009, brilliant blue G was used in scientific experiments to treat spinal injuries in laboratory rats.

[24] It acts by reducing the body's natural swelling response, which can cause neurons in the area to die of metabolic stress.

[28] In December 2019, brilliant blue G (under the trade name TissueBlue, DORC International, Netherlands) was approved for use in humans in the United States.

[32][33] The ability of the Coomassie dye to target amino acids with aromatic groups (phenylalanine, tyrosine, tryptophan) and basic side chains (lysine, arginine and histidine) allows the Bradford assay to be used for fingerprint analysis.