This substrate-chromogen contains 3,3',5,5'-tetramethylbenzidine (TMB). TMB Blue is for use in peroxidase-based, colorimetric techniques that call for the highest in sensitivity detection. TMB Blue is a stable, non-flammable and safe alternative to other peroxidase chromogens. This substrate-chromogen is recommended for peroxidase-based enzyme immunoassays. Upon oxidation, TMB forms a water-soluble blue reaction product that can be measured spectrophotometrically at 650 nm. Upon acidification, the reaction product becomes yellow with an
absorbance peak at 450 nm.