CF™640R Annexin V conjugate is Annexin V labeled with our superior far red fluorescent dye CF™640R. Annexin V is a 35-36 kDa protein that has a high affinity for phosphatidylserine (PS). In normal viable cells, PS is located on the cytoplasmic surface of the cell membrane. In apoptotic cells, however, PS is translocated from the inner to the outer leaflet of the plasma membrane, making itself available for Annexin V binding. CF™640R dye is brighter and far more photostable than Alexa Fluor® 647 when excited by the 633 or 635 nm laser, making CF™640R Annexin V an excellent choice for both flow cytometry and microscopy applications (download the CF™640R Flyer for more information).Compatible with the NucleoCounter® NC-3000™.