CFDA-SE (i.e. carboxyfluorescein diacetate succinimidyl ester) is a stable, cell-permeable dye, composed of a fluorescein molecule containing two acetate moieties and a succinimidyl ester functional group. After diffusion into the intracellular environment, cellular esterases remove the acetyl moieties from CFDA-SE, leaving behind CFSE (i.e. carboxyfluorescein succinimidyl ester) which covalently binds to amino groups on intracellular macromolecules by its succinimidyl group and can be retained within the cells for at least 8 weeks. CFSE stained cells can then be detected by fluorescence microscopy and flow cytometry under the excitation/emission maxima of 491/518 nm. CFDA-SE provides a valuable tool to quantify cell division and track cell migration, due to the sequential decrease in fluorescent labeling in daughter cells.
References:
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