The LIVE/DEAD™ BacLight™ Bacterial Viability and Counting Kit allows researchers to reliably distinguish and quantitate live and dead bacteria with the aid of a flow cytometer, even in a mixed population containing a range of bacterial types. This kit uses a mixture of two nucleic acid stains - green-fluorescent SYTO™ 9 dye and red-fluorescent propidium iodide - for viability determinations, and a calibrated suspension of microspheres for accurate sample volume measurements.

Any physiological buffer between pH 7.0–8.0, including PBS, can be used to dilute the SYTO dyes for the staining solution.