Cell & Organelle Stains

Tetrabromorhodamine 123 can be used to generate singlet oxygen (¹O₂) in mitochondrial membranes (1,2). The dye has a quantum yield for singlet oxygen generation of 0.65-0.7 and is particularly toxic to carcinoma cells.

DiOC16(3) is a green fluorescent lipophilic cyanine dye with two C16 hydrocarbon chains that can be used to stain cytoplasmic membranes.

DiB is a lipophilic cationically charged blue fluorescent dye.

Biotin-AM3-25 is a conjugate of AM3-25 and biotin. Membranes labeled with the probe can subsequently couple to avidin or streptavidin.

The fluorescence of octadecyl rhodamine B in membranes is quenched at high dye concentration but is released at dilution. This property makes the dye useful for membrane fusion assays.

NBD C6-ceramide (6-((N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoyl)sphingosine) has been used for following sphingolipid metabolism in cells, and as a selective stain for the Golgi apparatus in live and fixed cells.

NBD C6-sphingomyelin (6-((N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoyl)sphingosyl phosphocholine) has been used for following sphingolipid metabolism in cells.

The pKa of 5-carboxy-2′,7′-dichlorosulfonefluorescein is near 4 and thus the dye is potentially an excellent pH indicator for acidic organelles.

6-CFDA is membrane-permeant and thus can be loaded into cells via incubation. Once inside cells, 6-CFDA is hydrolyzed by intracellular esterases to 6-carboxyfluorescein.

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.

A far-red cell membrane-impermeant nuclear dye with greater nuclear specificity than Draq7™. Ideal for fixed cell nuclear counterstaining with minimal cytoplasmic RNA staining.

A red fluorescent dead cell stain for bacteria and mammalian cells