– Dextran-CY3 is a fluorescent labeling reagent combining the Cy3 fluorescent dye with Dextran. The Cy3 fluorophore is commonly utilized in applications such as immunolabeling, nucleic acid labeling, fluorescence microscopy, and flow cytometry. Cy3 has a maximum emission wavelength of approximately 562-570 nm. Dextran inhibits platelet aggregation and clotting factors, and is used as a plasma volume expander.