Iodonitrotetrazolium violet

C, Photometric assay for an alkaline phosphatase label using a cascade detection reaction. p-iodonitrotetrazolium violet. 

Cells separated by filtration from large aliquots of water can be visualized and counted on a 0.25 xm filter using the epifluorescent technique and a stain such as acridine orange. Stains such as fluorescein diacetate, 5-cyano-2,3-ditolyltetrazolium chloride or p-iodonitrotetrazolium violet indicate active metabolism by the formation of fluorescent products [9]. Antibody fluorescence microscopy is similar to general fluorescent microscopy, except that the fluorescent dye used is bound to antibodies specific to SRBs. Only bacteria recognized by the antibodies fluoresce. Results can be analyzed within two hours. The technique detects viable and nonviable bacteria but it is limited to the type of SRB used in the manufacture of these antibodies [19]. 

Haghighi, A. Z. Wei, R. Measurement of superoxide dismutase in erythrocytes and whole blood using iodonitrotetrazolium violet. Anal Lett. 1998, 31, 981-990. 

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