7-AAD (7-Aminoactinomycin D), 500 tests

A fluorescent cell viability dye supplied by STEMCELL Technologies, 7-AAD (7-Aminoactinomycin D) is a DNA-intercalating compound with strong affinity for double-stranded DNA. It is excluded from live cells with intact membranes but penetrates dead or damaged cells, making it widely used to differentiate and exclude non-viable cells in flow cytometric analysis. The dye has a molecular weight of 1270.4 g/mol.

It is often employed as an alternative to propidium iodide, offering minimal spectral overlap with blue, green, and many red fluorophores, including phycoerythrin (PE) and fluorescein isothiocyanate (FITC). The dye can be excited using 488 nm (blue), 532 nm (green), and 561 nm (yellow-green) laser lines, with excitation maxima reported at 546 nm (DNA complex) and 503 nm (free form), and emission maxima at 647 nm (DNA complex) and 675 nm (free form).

Beyond viability staining, 7-AAD is used in DNA fluorescence imaging to discriminate early and late stages of apoptosis, in cell-mediated cytotoxicity studies, and for chromosome banding analysis. The compound has also been reported to exhibit antibacterial properties and growth-inhibitory activity against certain leukemias and sarcomas. It is supplied in phosphate-buffered saline, pH 7.2, containing 0.09% sodium azide, and should be stored at 2 - 8°C without freezing, protected from prolonged exposure to light. The product has been verified for viability assessments of cells isolated with EasySep™ and RosetteSep™ kits.