Discussion

DRAQ7™ is derived from the proven cell-permeant, far-red fluorescing DNA-binding probe DRAQ5™. DRAQ7 is truly cell impermeant yet retains the DNA targeting and far-red fluorescence of the parent chromophore. DRAQ7 shows remarkably low toxicity as described by internal data, ultra-sensitive bioassays for DNA intercalators, more recent publications on ex-plant tissue culture and nano-particle toxicity, and importantly in the presence of toxicants or anti-cancer compounds. Thus, cells can be exposed to it at any stage of an assay to permit real-time monitoring of loss of membrane integrity (in apoptosis, death). Being DNA specific it allows monitoring cell—by-cell while its spectral properties mean it can be incorporated into multi-colour experiments, or with Hoechst 33342 or CyTRAK Orange (for simple cell health assays) or with mitochondrial membrane potential probes such as TMRM. It can be used on HCS imaging platforms, fluorescence microscopes, cytometers and sorters. It is ready-to-use in aqueous from the fridge.