Scientific presentations at the HCA Europe conference in Prague confirm the nucleic acid-binding dye DRAQ5 as counterstain of choice for cell-based imaging HCS assays. DRAQ5 rapidly enters live or fixed cells to intensity discriminate between nuclear and cytoplasmic compartments. The resulting differential is ideal for compartment segmentation by automated image analysis tools. This offers new opportunities for cell-based assays where cell location, cell perimeter, cell shape and cell spread parameters can be used to define the
assay at the single cell. DRAQ5 permits the reliable tracking of fluorophore-tagged protein translocations and expression changes in GPCRs, kinases and other therapeutic targets in drug discovery and in vitro toxicology.