Tetrazolium chloride
Triphenyl tetrazolium chloride, TTC, or simply tetrazolium chloride is a redox indicator commonly used in biochemical experiments especially to indicate cellular respiration. It is a white crystalline powder, soluble in water, ethanol and acetone but insoluble in ether.In the TTC assay, TTC is used to differentiate between metabolically active and inactive tissues. The white compound is enzymatically reduced to red TPF in living tissues due to the activity of various dehydrogenases, while it remains in its unreacted state in areas of necrosis since these enzymes have either denatured or degraded.
TTC has been employed in autopsy pathology to identify myocardial infarctions. Healthy viable heart muscle will stain deep red from the cardiac lactate dehydrogenase, while areas of potential infarctions will be more pale.