HiLyte Fluor™ 405-streptavidin conjugate has been optimized in fluorophore/protein labeling ratio to ensure high fluorescent signal and uncompromised streptavidin function. HiLyte Fluor™405 is a new blue fluorescent dye with the structure designed for maximum brightness when conjugated to macromolecules. The fluorescence signal of HiLyte™405 can be observed with excitation and emission wavelengths at 404/428 nm.