Iodonitrotetrazolium chloride

CAS: 146-68-9

Ref. 3D-I-7630

Product Information

• Name: Iodonitrotetrazolium chloride
• Synonyms: p-Iodonitrotetrazolium Violet, INT, 2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-phenyl-2H-tetrazolium chloride
• Brand: Biosynth
• Description: The monotetrazolium salt Iodonitrotetrazolium chloride (INT), first described by Atkinson et al. (1950), is an iodinated derivative of TTC (2,3,5-Triphenyltetrazolium chloride) with an absorption λmax of 248 nm. The color produced by reduction of this iodonitro compound is a red to purple or brownish formazan with an absorption maximum at 485 to 492 nm (depending on the solvent). INT is often used to visualize dehydrogenase activity histochemically as well as in Western blot staining and as a staining agent for agar colony formation assays. NAD or NADP-dependent dehydrogenases activity assays: NAD+- or NADP+-dependent dehydrogenase transfers electrons from a substrate (the electron donor, e.g. succinate) to NAD+ or NADP+, forming NADH and NADPH, respectively. Then, the final transfer of hydrogen to the tetrazolium salt is catalyzed by NADH or NADPH dehydrogenases (e.g. succinate dehydrogenase), leading to the reduction of INT and formation of the water-insoluble INT-formazan. 1 mol of formazan is produced for each mole of succinate utilized in the presence of INT. It is important to mention for applications in histology, that INT-formazan precipitates at the site of this latter dehydrogenase but not at the site of the original NAD+- or NADP+-dependent dehydrogenase activity.

Chemical properties

• Molecular weight: 505.7 g/mol
• Formula: C₁₉H₁₃ClIN₅O₂