Cyanine 5 NHS ester tetrafluoroborate

Cyanine 5 NHS ester tetrafluoroborate (Cy5) is a reactive fluorescent dye with an excitation maximum at 638 nm, used for labeling proteins, antibodies, and nucleic acids. It is widely applied in fluorescence microscopy, flow cytometry, and in vivo imaging for both in vitro and in vivo research applications.