TMB (3,3',5,5'-tetramethylbenzidine) chromogen solution can Used as a substrate for horseradish peroxidase (HRP) in ELISA.

Using TMB

Use this reagent as received without dilution or further preparation. In the presence of peroxidase (HRP, POD), TMB will be converted into a blue color that can be read at OD₆₅₀ nm.