AAT Bioquest's MycoLight™ Fluorescence Live/Dead Bacterial Imaging Kit provides two-color fluorescence assay for visualizing live and dead bacteria through fluorescent microscope. MycoLight™ 520 is a non-fluorescent esterase substrate that diffuses into both Gram positive and Gram-negative bacteria. Upon hydrolysis by bacterial intracellular non-specific esterases, a green fluorescent product is produced and accumulated within bacteria. In contrast, propidium iodide is a red-fluorescent nucleic acid stain that only penetrates bacteria with damaged membranes. Thus, with an appropriate mixture of the MycoLight™ 520 and propidium iodide stains, live bacteria with intact cell membranes emits green fluorescence, whereas dead bacteria with damaged membranes gives red fluorescence. The MycoLight™ Fluorescence Live/Dead Bacterial Imaging Kit is a robust tool for imaging Live/Dead bacteria. Stained cells can be monitored fluorimeterically (FITC filter set) and (TRITC filter set) for live and dead bacteria respectively.