2,3,5-Triphenyl-tetrazolium chloride solution

2,3,5-Triphenyl-tetrazolium chloride (TTC) is a dye largely used for the easy enumeration of microbial colonies in solid culture media. This dye is colorless in the oxidized form and changes to red when reduced by microorganisms, due to the formation of formazan. Live microorganisms, for example, E. coli and other coliforms reduce TTC by enzymatic action, forming red color formazan that is kept inside granules in the cells. TTC is highly recommended in testing pasteurized milk because there is a high percentage of microorganisms unable to reduce TTC in pasteurized milk, which cannot be detected by laboratory procedures. Higher concentrations of TTC may have an inhibitory effect on the growth of Gram-positive organisms.

2,3,5-Triphenyl-tetrazolium chloride (TTC) solution is a redox indicator that can help indicate cellular respiration and identify viable and non-viable cells as well as identify microorganisms capable of reduction of TTC on solid culture media

(per vial)
2,3,5-Triphenyl tetrazolium chloride: 0.1 g, distilled water: 10 ml