1,3,5-Triphenylformazan TCI T0175

TCI 1,3,5-Triphenylformazan (CAS 531-52-2) is a deep red formazan compound. It is the reduction product of 2,3,5-triphenyltetrazolium chloride (TTC). In the laboratory it is an important reference standard for TTC-based assays. In these assays, dehydrogenase enzymes in living cells reduce colourless TTC to the red formazan. With pure triphenylformazan on hand, researchers can build calibration curves, which turn a visual colour reaction into an accurate quantitative result. This makes it a key reagent for any laboratory that measures biological activity with tetrazolium chemistry.

The main advantage of 1,3,5-triphenylformazan is its intense, stable colour. Once extracted into a suitable organic solvent, its colour intensity can be measured by spectrophotometry. The compound is the same end product that forms in the test samples, so a standard curve made from it reflects the true response of the TTC assay. This avoids the uncertainty that comes from using an unrelated dye as a substitute standard. Apart from its use as a standard, the compound is classified as a research dye and as a reference material for studies of formazan and azo compound chemistry.

In Indonesia, triphenylformazan is especially relevant to agricultural, soil science, forestry, and seed technology laboratories. Measuring soil dehydrogenase activity with the TTC method is a common way to assess the microbial activity and biological health of soils, including agricultural land, plantations, and forest soils. University research groups, government research institutes, and quality control laboratories that run tetrazolium-based assays rely on a reliable formazan standard. It lets them produce consistent results that can be compared across studies.

• Soil dehydrogenase activity assays: the compound is used to prepare calibration curves, so the red formazan formed from TTC in soil samples can be accurately quantified as a measure of microbial activity.
• Calibration in TTC-based viability assays: because it is the same end product that forms in the samples, standards made from it reflect the true colorimetric response of the assay.
• Spectrophotometric method development: its intense and stable colour after solvent extraction makes it well suited to setting up and validating absorbance-based measurement procedures in research laboratories.
• Seed and plant tissue studies using tetrazolium chemistry: seed technology and agricultural laboratories can use it as a reference to interpret and quantify red formazan formation in living tissue.
• Research on formazan and azo compound chemistry: as a classified research dye and reference material, it serves as a well-defined comparison compound for studies of colour chemistry and structure.

Store 1,3,5-Triphenylformazan in its original, tightly closed container in a cool, dry, well-ventilated place. Protect it from direct light, heat, and moisture so that its colour and quality as a reference standard stay intact. Use clean, dry spatulas and glassware when weighing, and reseal the container promptly after use. Handle the compound according to good laboratory practice: wear a lab coat, safety glasses, and gloves, avoid creating or breathing in dust, and avoid contact with skin and eyes. Use a fume hood when preparing solutions with organic solvents. Before use, read the Safety Data Sheet (SDS) supplied by the manufacturer, and dispose of waste according to your institution's rules and local regulations.

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