This CF™640R tyramide conjugate is used for tyramide signal amplification (TSA)1,2,3, which is an enzyme-mediated detection method that uses horseradish peroxidase (HRP) to generate high-density labeling of a target protein or nucleic acid in situ. A tyramide conjugate is incubated in the presence of HRP (often bound to a secondary antibody), which catalyzes the binding of the tyramide (and associated label) to adjacent tyrosines for enhanced fluorescent signal. CF™640R is a novel rhodamine-based dye spectrally very similar to Cy®5 and Alexa Fluor® 647. CF™640R is much brighter than Cy®5 and at least as bright as Alexa Fluor® 647 when excited at 633 or 635 nm. However, the most important advantage of CF™640R is its exceptional photostability. CF™640R is far more photostable than the cyanine-based dyes Cy®5 and Alexa Fluor® 647. It is also more photostable than Atto 647N, a dye that has been extensively used in single molecule-based imaging.Compatible with the NucleoCounter® NC-3000™.