Cy3Dextran (MW 40000) is a fluorescent labeling agent that combines 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 serves as a plasma volume expander and inhibits platelet aggregation and coagulation factors [Ex/Em = 550/570 nm].