Chloride, pH, Zinc & Other Indicators

Flubida-2 has been used to detect pH at a specific site in a cell such as cell organelles by directing the probe to where avidin fusion proteins are located. The probe is a conjugate of biotin and fluorescein diacetate, which is nonfluorescent until the probe has entered the cells and hydrolyzed by endoesterases.

5-CFDA is membrane-permeant and thus can be loaded into cells via incubation. Once inside cells, 5-CFDA is hydrolyzed by intracellular esterases to 5-carboxyfluorescein (see 50015).

This dye can be used as a low pH indicator similar to 51015, and is also useful as a general green fluorescent label.

5-(and-6)-carboxy-2′,7′-dichlorofluorescein is similar to carboxyfluorescein (51013), but has lower pK_a. It is useful for detecting pH in more acidic environment.

5-(and-6)-Carboxy-2′,7′-dichlorofluorescein diacetate is membrane-permeant and thus can be loaded into cells via incubation. The diacetate is readily hydrolyzed to 5-(and-6)-carboxy-2′,7′-dichlorofluorescein (51015) by intracellular esterases.

5-(and-6)-FAM (full name: 5-(and-6)-Carboxyfluorescein mixed isomer) has a pKa of 6.5 and can be used as a pH indicator.

Furaptra, AM ester is a membrane-permeant form of Furaptra (Mag-Fura-2). The indicator is loaded into cells via simple incubation.

Mag-Fura-2 is a UV-excitable fluorescent indicator for magnesium with a K_d of 1.9 mM (1,2).

Mag-Fura-2 is a UV-excitable fluorescent indicator for magnesium with a K_d of 1.9 mM.

BCECF (2′,7′ –bis-(Carboxyethyl)-5-(and-6)-carboxyfluorescein) is the most widely used fluorescent pH sensor. Because its pK_a (6.97) is close to physiological pH, BCECF can detect cytosolic pH change with high sensitivity.

BCECF, AM ester is membrane-permeant and thus can be loaded into cells via incubation. This product is a mixture of three molecular species, all of which are readily hydrolyzed by endogenous esterases into a single BCECF free acid form once they are in the cells.

BCECF, AM ester is membrane-permeant and thus can be loaded into cells via incubation. This product is a mixture of three molecular species, all of which are readily hydrolyzed by endogenous esterases into a single BCECF free acid form once they are in the cells.