Definition: Quaternary salts derived from tetrazoles. They are used in tests to distinguish between reducing sugars and simple aldehydes, for detection of dehydrogenase in tissues, cells, and bacteria, for determination of corticosteroids, and in color photography. (From Mall's Dictionary of Chemistry, 5th ed, p455)
5-cyano-2,3-ditolyltetrazolium [ 5-CTC cpd,5-cyano-2,3-ditolyl tetrazolium chloride,5-cyano-2,3-ditolyltetrazolium chloride,5-cyano-2,3-tolyl-tetrazolium chloride ] a fluorescent redox probe used to provide direct visualization of actively respiring bacteria