Viability Assay Kit, Green/Red Fluorescence provides a convenient and robust method to determine cell viability through the use of two fluorogenic dyes (Calcein AM and Propidium Iodide) that permit the simultaneous detection and distinction of viable and non-viable cells. As a fluorogenic dye, Calcein AM is initially non-fluorescent. After its passive entry into cells, intracellular esterases which are present only in viable cells, hydrolyze Calcein AM into Calcein, a bright green fluorescent molecule (Bratosin et al.). The intensity of the green fluorescence is proportional to the amount of esterase activity and thus can correlate to the number of viable cells. Propidium Iodide is the second fluorogenic dye; however, unlike Calcein AM, can only cross the compromised membranes of dead cells. Once inside dead cells, Propidium Iodide fluoresces red upon its binding to DNA. The dyes in this kit are well suited for use with fluorescence microscopes or fluorescence microplate readers that are capable of detecting in the FITC (for Calcein) and TRITC (for Propidium Iodide) channels.

Use Cell Viability Assay Kit, Green/Red Fluorescence to detect and quantify cell proliferation in adherent or suspension cultures or incorporate it as a useful readout in your in vitro cytotoxicity assays.