5(6)-FAM SE (full name: 5-(and-6)-Carboxyfluorescein, succinimidyl ester mixed isomers) is an amine-reactive green fluorescent dye widely used for labeling proteins or other molecules that contain a primary or secondary aliphatic amine. The coupling reaction is usually carried out at pH 8-9.5. The amide linkage from the coupling reaction is much more stable than the thiourea linkage formed from the coupling of an amine and an isothiocyanate. &lamba;Ex/&lamba;Em = 495/519 nm Yellow solid soluble in DMSO or DMF Store at -20°C and protect from light C25H15NO9 MW: 473.4 [117548-22-8]