AAT Bioquest

What are cyanine dyes used for?

Posted July 1, 2021


Cyanine dyes are a class of fluorescent dyes. They are used to label amine groups on peptides, antibodies, oligonucleotides, or nucleic acids. Labeling is done for visualization and quantification purposes. Cyanine dyes are suitable for use in a wide range of fluorescence detection techniques including flow cytometry, microscopy, and fluorescence resonance energy transfer (FRET).

There are several different cyanine dyes. Each one differs with respect to their molecular structure, charge, and membrane permeability.

Additional resources

Cyanine Polyene Reactivity: Scope and Biomedical Applications


Cyanine 5.5 monosuccinimidyl ester [equivalent to Cy5.5® NHS ester]