Application 3,3′,5,5′-Tetramethylbenzidine (TMB) is a noncarcinogenic substitute (Ames test negative) for benzidine1 suitable as peroxidase substrate for use in ELISA procedures. The substrate produces a soluble end product that is pale blue in color and can be read spectrophotometrically at 370 or 620-650 nm. The TMB reaction may be stopped with 2 M H2SO4 (resulting in a yellow color), and read at 450 nm. A sensitive and specific reagent for the detection of blood,2 assay of hemoglobin,3,4,5 assay of peroxidases.6,7,8 Other Notes Standard for determining aromatic amines released from azo-dyes in commodities9 |