Description General description 3,3′-diaminobenzidine-tetrahydrochloride-dihydrate (DAB) is toxic in nature, and is one of the most potent marker being used in immunochemistry, mostly at the electron and light microscope levels. Application 3,3′-diaminobenzidine-tetrahydrochloride-dihydrate (DAB) was used as a chromogen, for detecting the antigen-antibody complex. Packaging 1, 5, 25 g in glass bottle Other Notes Reagent for the spectrophotometric determination of selenium; Peroxidase stain. Differentiation between two classes of mycobacterial catalase in polyacrylamide electrophoresis gels; Specific indication of hemoproteins in polyacrylamide gels by double staining