This dye can be used as a low pH indicator similar 5-and-6-Carboxy-2'7'-dichlorofluorescein, and is also useful as a general green fluorescent label. Carboxy-2',7'-dichlorofluorescein is significantly more photostable than carboxyfluorescein.
&lamba;Ex/&lamba;Em = 504/529 nm (pH 8)
ε = 90,000
Yellow solid soluble in DMSO, DMF or basic water (pH >7)