Description
BD Pharmingen™ Calcein Blue AM is used for labeling live cells that can be detected and further analyzed by flow cytometry. The enhanced hydrophobicity provided by the acetomethoxy (AM) group allows this dye to readily enter viable cells. Once inside, intracellular esterases cleave the AM groups off of the weakly fluorescent Calcein Blue AM, trapping fluorescent Calcein Blue within the cell. Since dead cells lack esterase activity, only viable cells are labeled. Calcein Blue is optimally excited at the 360 nm wavelength of light that can be provided by an ultraviolet laser and emits maximally at 445 nm. This dye can also be excited by the violet laser.