5/6 FAM mixed isomers

The mixed isomers 5/6-FAM (5/6-Carboxyfluorescein) is an amine-reactive derivative of Fluorescein > giving stable derivatives upon conjµgation with biopolymers. The amine-reactive fluorescein derivatives 5-FAM > and 6-FAM > and the mixed isomers form 5/6-FAM > are the most common fluorescent derivatizing reagents for the covalently labeling of proteins. Carboxyfluorescein can be retained much better in cells than fluorescein since its pKa is lower than the cytosolic pH of most cells. 6-FAM contains a carboxylic acid which can react with primary amines via carbodiimide activation. Carboxyfluorescein is commonly used as a polar tracer.
Other fluorescent dyes from Genaxxon: TAMRA >, ROX >, DAF-2 >