DCFH; 2',7'-Dichlorodihydrofluorescein diacetate,

 2-[3,6-Bis(acetyloxy)-2,7-dichloro-9H-xanthen-9-yl]benzoic acid; o-(2,7-Dichloro-3,6-dihydroxyxanthen-9-yl)benzoic acid diacetate

Cell permeable reagent for use in detection of peroxidase activity.

Cell-permeable ROS probe.  Reduced derivative of 2',7'-dichlorofluorescein. Can detect reactive oxygen species in live cells. Detects peroxidase activity (oxidative metabolism, intracellular regulation of  ROS or oxidative burst). Upon enzyme activity, the highly fluorescent dye 2',7'-dichlorofluorescein is produced (Ex/Em = 495/529 nm).

DCFH (commonly known as dichlorofluorescin) is used as an indicator of peroxynitrite formation. DCFH is supplied as the diacetate ester. Following enzymatic or base-catalyzed cleavage of the diacetate groups, it is readily oxidized to the highly fluorescent product dichlorofluorescein (DHF). Peroxynitrite is an efficient mediator of this oxidation and neither NO, superoxide, nor hydrogen peroxide alone appear to oxidize DCFH. Formation of DHF can be monitored by fluorescence spectroscopy using excitation and emission wavelengths of 502 and 523 nm, respectively, or by absorbance spectroscopy at 500 nm (ɛ = 59,500 M−1cm−1).

H2DCFDA is a fluorescent cell permeabl ROS indicator.