This CF™405S 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™405S (Ex/Em = 404/431 nm) is a blue fluorescent dye with an absorption peak wavelength that nearly coincides with the 405 nm blue diode laser line. In addition, the emission peak wavelength of the dye well centers within the blue detection window of BD flow cytometers. As a result, flow cytometry analysis using CF™405S dye results in much brighter signal than that using Alexa Fluor® 405.