Researchers from the North East Stem Cell Institute, Newcastle, UK presented data at the recent ISAC2008 congress on the nucleic acid-binding dye CyTRAK Orange describing its utility in flow cytometry applications. In the poster, Dimmick et. al, state that CyTRAK Orange allows them to report more accurate phenotype percentages by using the dye as a DNA-enabled gate excluding any debris from analysis. This also offers an alternative to CD45 gating particularly where cells of interest are CD45 negative, demonstrated with circulating epithelial cells seeded into blood. Further, the dye avoids need for RBC lysis of a whole blood sample, which can destroy antigens under investigation or may lead to unwanted lysis. The authors show further examples with human peripheral blood, mouse bone marrow and mouse embryonic stem cells. The spectral profile of CyTRAK Orange (EXmax 510nm / EMmax 610nm) permits convenient co-excitation with FITC and PE-Cy7 with the blue argon-ion laser line whilst it is not excited by the 633 nm line or above. Live (or fixed) nucleated cells are simply and rapidly stained with CyTRAK Orange in a few minutes and permit a convenient no-lyse, no-wash procedure immediately prior to analysis.