Description
General Description
Cy5-NHS Ester is a widely used amine-reactive fluorescent dye designed for covalent labeling of biomolecules. The Cyanine 5 fluorophore exhibits bright near-infrared fluorescence with excitation and emission maxima of approximately 649 nm and 670 nm, respectively, providing excellent sensitivity, low background autofluorescence, and superior tissue penetration compared with visible fluorophores.
The activated NHS ester rapidly reacts with primary amines under mild aqueous conditions (typically pH 7.2–8.8), producing stable amide bonds with lysine residues on proteins, peptides, antibodies, enzymes, amino-modified oligonucleotides, polymers, nanoparticles, and other biomolecules.
Cy5-NHS Ester is extensively employed in fluorescence microscopy, flow cytometry, in vivo imaging, immunofluorescence, biosensor fabrication, nanoparticle labeling, drug delivery research, and molecular diagnostics.
Applications
- Protein labeling
- Antibody labeling
- Peptide labeling
- Oligonucleotide labeling
- Polymer labeling
- Nanoparticle labeling
- Fluorescence microscopy
- Flow cytometry
- In vivo imaging
- Molecular diagnostics
Features and Benefits
- Bright near-infrared fluorescence
- High photostability
- Reactive NHS ester
- Rapid amine-selective conjugation
- Stable amide bond formation
- Low biological autofluorescence
- Excellent aqueous sensitivity
- Research-grade quality








