Green Live/Dead Stain

Green Live/Dead Stain (catalog #6342) is a vital dye that exhibits intact cell membrane exclusion properties analogous to the popular red fluorescing vital dyes, Propidium Iodide (PI), 7-amino- actinomycin D (7-AAD) and DRAQ7. Like the red fluorescing dyes, Green Live/Dead Stain is excluded from intact, healthy cells due to its polar nature. In the presence of cells exhibiting compromised membrane integrity, Green Live/Dead Stain penetrates the cell and nuclear membrane barriers and intercalates tightly to DNA in a manner analogous to PI and 7-AAD. When bound to DNA, it acquires a greatly enhanced fluorescence potential (>2000X) in the green emission range. These important vital dye properties enable Green Live/Dead Stain to be used in flow cytometry-based protocols to assess the percentage of late apoptotic, necrotic, and membrane-compromised cells within a sample cell population. When bound to nucleic acids, the maximum absorption of Green Live/Dead Stain is 495 nm and the maximum emission is 512 nm (Figure 1). Cells can be viewed through a fluorescence microscope (Figures 2 & 5) or analyzed with a flow cytometer (Figure 4). Green Live/Dead Stain is provided as a 500 µM concentrated stock solution dissolved in DMSO. For flow cytometry applications, a staining concentration of 50 nM is recommended. Therefore, using sample sizes of 0.5 mL, a single 50 µL vial (catalog #6342) provides enough reagent for 1000 tests. For fluorescence microscopy applications, a usage concentration of 0.5 µM is suggested. In this way, a vial is sufficient for 100 tests (0.45 mL sample sizes). Green Live/ Dead Stain can be used with ICT’s red FLICA660 caspase inhibitor reagents (e.g., catalog #9120) to identify four populations of cells: living; early apoptotic; late apoptotic; and necrotic (Figures 4 & 5).