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Ionisation: Basic

Chemical structure of Iodonitrotetrazolium

Common Name: INT
Suggested Name: Iodonitrotetrazolium
Other Names:

C.I. Number:
C.I. Name:
Color: Red
Solubility Aqueous: Soluble
Solubility Ethanol: Soluble
Absorption Maximum:
Empirical Formula: C19H13N5O2ICl
Formula Weight: 505.7


Iodonitrotetrazolium chloride has been used to visualize dehydrogenase enzyme activity histochemically. As the enzyme removes hydrogen from the substrate it is transferred to a hydrogen acceptor, usually a co-enzyme. From the co-enzyme, it is transferred to the tetrazole, which is consequently reduced to its insoluble and intensely colored formazan. The formazan of INT is red.


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    Conn’s Biological Stains
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  2. Aldrich chemical catalogue, 1992
    Aldrich Chemical Company, Milwaukee, WI, USA.
  3. Burstone, M.S.
    Enzyme Histochemistry and its application to the study of neoplasms
    Academic Press, New York, NY, USA