This product is a solution containing Coomassie Brilliant Blue (CBB) G-250, which is used to measure protein concentrations in solution using the Bradford method. When CBB binds to a protein under acidic conditions, the maximum absorption wavelength shifts from 465 to 595 nm. This change in absorbance can be used to determine protein concentrations in solution. Surfactant in the measurement sample does not affect the measurement if the concentration is below a certain level (see the effects of coexisting substances, described below).