Cy3Dextran (MW 20000) is a fluorescent labeling reagent that combines 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. Dextran inhibits platelet aggregation and clotting factors, serving as a plasma volume expander (Ex/Em = 550/570 nm).