5(6)-CFDA, SE (full name: 5-(and-6)-Carboxyfluorescein diacetate, succinimidyl ester, also known as CFSE) is a useful fluorescent tracer that can passively diffuse into cells and covalently label intracellular proteins, resulting in long-term cell labeling. The reagent itself is colorless and non-fluorescent but becomes brightly green fluorescent once it is hydrolyzed by intracellular esterases. The labeling has been shown to be stable to formaldehyde or gluteraldehyde fixation. Also see our CFDA SE Cell Proliferation Assay Kit.    &lamba;Ex/&lamba;Em (of hydrolysis product at pH 7) = 495/519 nm  White solid soluble in DMSO or DMF  Store at -20°C and protect from light  C29H19NO11  MW: 557  [150347-59-4]