5(6) Carboxyfluorescein succinimidyl ester / 5(6) FAM-SE

This amine-reactive fluorescein derivatization reagent is widely used for covalent labeling of proteins and alkylamino modified nucleic acids.

Fluorescein has an excitation maximum that closely matches the 488 nm spectral line of the argon-ion laser, making it the predominant fluorophore for confocal laser scanning microscopy and flow cytometry applications. It has a relatively high absorptivity, excellent fluorescence quantum yield, and good water solubility. Importantly, protein-fluorescein conjugates are not inordinately susceptible to precipitation.