Thermo Fisher, C369, Carboxy-DCFDA (5-(and-6)-Carboxy-2',7'-Dichlorofluorescein Diacetate), mixed isomers

Carboxy-DCFDA is a cell-permeant fluorescein derivative supplied as mixed 5- and 6-carboxy isomers for fluorescence-based cellular measurements. This configuration contains 100 mg of solid dye. The nonfluorescent diacetate form can passively enter cells, where intracellular esterases remove the acetate groups to generate fluorescent carboxy-dichlorofluorescein. The resulting fluorophore has excitation and emission maxima near 504 and 530 nm. With a pKa of approximately 4.8, the dye can be used as an acidic pH-sensitive fluorescent probe and has also been used in cell-based oxidative-stress research. Concentrated stock solutions can be prepared in anhydrous DMSO, DMF, or ethanol. Prepared stocks should be used promptly, while the unopened dye is stored frozen at approximately −5 to −30 °C and protected from light.