Ex (nm): 543
Em (nm): 712
LDS 751 is a fluorescent cell-permeant nucleic acid stain that can be well excited with 488 nm laser line although it has a peak excitation at ~543 nm on dsDNA. It might be an alternative to DRAQ 5 , useful in multicolor analyses due to its long wavelength emission maximum (~712 nm). Upon binding to dsDNA of LDS 751 has ~20-fold fluorescence enhancement. It has been reported that LDS-751 is excluded from the nucleus and binds the polarized membranes of mitochondria. Thus cautions need be taken when LDS 751 is used for analyzing live cells and LDS-751 fluorescence as being indicative of nuclear status. Thiazole orange (an RNA dye) and LDS-751 (a DNA dye) composition has been used to separate reticulocytes from other cell populations. LDS 751 has been also used to separate red blood cells from nucleated cells.