Cell viability dyes for flow cytometry

Dead cells can give rise to false positives in flow cytometry experiments due to autofluorescence and increased non-specific binding. It is important to eliminate these dead cells from your flow cytometry data analysis.

​​Several markers, including cellular DNA, cellular esterase, and cellular primary amines, can be used to distinguish between dead and live cells.

Explore our ranges of easy-to-use cell viability kits and have confidence in your flow cytometry results.

DNA binding dyes

Membrane-permeable esterase-activated dyes are widely used to label live cells. These dyes are non-fluorescent, with a cell-retaining moiety. Upon entering cells, the dye becomes fluorescent following hydrolysis facilitated by intracellular esterases. These modified dyes are trapped in cells by intact cell membranes. In some cases, hydrolyzed dyes further react with other intracellular components, forming irreversible labels. Dead cells are not stained by these dyes due to the lack of metabolically active esterases and intact cell membranes.

Membrane-permeable esterase-activated cell viability dyes

Membrane-permeable esterase-activated dyes are widely used to label live cells. These dyes are non-fluorescent, with a cell-retaining moiety. Upon entering cells, the dye becomes fluorescent following hydrolysis facilitated by intracellular esterases. These modified dyes are trapped in cells by intact cell membranes. In some cases, hydrolyzed dyes further react with other intracellular components, forming irreversible labels. Dead cells are not stained by these dyes due to the lack of metabolically active esterases and intact cell membranes.

Amine-reactive fixable cell viability dyes

Amine-reactive viability dyes react with free primary amines found in cells. As these dyes are membrane-impermeant, live cell intracellular amines exclude the dye, leading to a significant fluorescence intensity difference between live and dead cells. The irreversible reaction of these dyes with amine makes them compatible with post-staining cell fixation and permeabilization. This characteristic makes these dyes useful when following an intracellular staining protocol.