Description:
Allows fast and easy measurement of both living and dead cells by measuring intracellular esterase activity (live cells) and staining of nucleic acids in chromatin (dead cells) in vitro, and in cell culture.

Application:
Esterases are a family of catabolic enzymes that cleave esters in a wide range of naturally occuring substrates intracellularly. They are ubiquitous to almost all living organisms. Esterase activity can be used to monitor viability of living cells using the fluorescent substrate 5(6)-carboxyfluorescein diacetate contained in the kit. Upon cleavage, the fluorescent product 5(6)-carboxyfluorescein (green fluorescence color) is released and activity measurements are easily obtained either in vitro, in cell preparations, or in vivo. The kit also contains the DNA stain, propidium iodide  that is membrane impermeant to live cells, but can enter the nucleus of dead cells and stain the chromatin (red fluorescence color). Measurement of red versus green fluorescence gives an accurate measurement of dead versus live cell number (viability). The kit contains enough substrate solutions for hundreds of assays and control experiments, and also contains reference standards and a detailed protocol for use. See the references below for more information and applications.