Nuclear Green™ Fixable DCS1 is a fluorogenic, DNA-selective and cell-impermeant dye for analyzing DNA content in dead, fixed or apoptotic cells. It is optimized for surviving cell fixation process better than the common DNA dyes such as PI, DAPI, Hoechst, 7-AAD, DRAQ-5, DRAQ-7 or SYBR Green. It contains a DNA-reactive group, thus covalently bonds with DNA. Nuclear Green™ Fixable DCS1 has its green fluorescence significantly enhanced upon binding to DNA. It can be used in fluorescence imaging, microplate and flow cytometry applications. This DNA-binding dye might be used for multicolor analysis of dead, fixed or apoptotic cells with proper filter sets.