TMB reagents containing 3,3',5,5'-tetramethylbenzidine (TMB), a chromogenic substrate for horseradish peroxidase (HRP). During the enzymatic degradation of hydrogen peroxide by HRP, TMB forms a water-soluble blue byproduct that can be measured spectrophotometrically at 650 nm. Acidification with a stop solution of sulphuric acid (H2SO4) renders a yellow color with absorption peak at 450 nm.
For Research Use Only. Not for use in diagnostic procedures.