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dichlorofluorescein

n. (context organic compound English) A chlorinated derivative of fluorescein formed from dichlorodihydrofluorescein when used as an indicator of peroxynitrite formation

Wikipedia
Dichlorofluorescein

Dichlorofluorescein (DCF) is an organic dye of the fluorescein family, being substituted at the 2 and 7 positions by chloride.

It is used as an indicator for argentometry by Fajans method.

It is also used in the cellular antioxidant activity (CAA) assay. Dichlorofluorescin is a probe that is trapped within cells and is easily oxidized to fluorescent dichlorofluorescein. The method measures the ability of compounds to prevent the formation of DCF by 2,2'-Azobis(2-amidinopropane) dihydrochloride (ABAP)-generated peroxyl radicals in human hepatocarcinoma HepG2 cells.