Description

Cyanine 5 Nhs Ester is a near-infrared fluorescent labeling reagent widely used for the covalent conjugation of biomolecules. Its core value lies in its high reactivity with primary amines, enabling the stable, site-specific tagging of proteins, antibodies, peptides, and oligonucleotides for advanced detection and imaging. This product is essential for researchers and manufacturers in the fields of bioconjugation, flow cytometry, fluorescence microscopy, and in vivo imaging, where bright, photostable near-infrared signals are required.

Application

• Antibody and Protein Labeling: Conjugation to monoclonal antibodies, streptavidin, and other proteins for immunoassays (ELISA, Western blot) and diagnostic kit development.
• Flow Cytometry & Cell Analysis: Tagging of cell surface markers or intracellular proteins for multicolor flow cytometry and high-content screening applications.
• Fluorescence Microscopy & Imaging: Preparation of fluorescent probes for fixed and live-cell imaging, super-resolution microscopy, and tissue section staining.
• In Vivo Imaging Probes: Development of targeted imaging agents for preclinical research in oncology, inflammation, and biodistribution studies due to its deep tissue penetration.
• Nucleic Acid Labeling: Labeling of amino-modified oligonucleotides, DNA, or RNA for fluorescence in situ hybridization (FISH) and genomic detection.
• Biomaterial and Nanoparticle Functionalization: Covalent attachment to amine-functionalized microspheres, dendrimers, or nanoparticles to create fluorescent tracking tools.

Basic Information

Product Name	Cyanine 5 Nhs Ester
CAS No.	1263093-76-0
Molecular Formula	C37H42N3O5+
Molecular Weight	608.75 g/mol (as cation)
Synonyms	Cy5 NHS Ester; Cy5 N-Hydroxysuccinimide Ester; Sulfo-Cyanine5 NHS ester (non-sulfonated form); 1-(5-Carboxypentyl)-1'-ethyl-3,3,3',3'-tetramethylindocarbocyanine N-hydroxysuccinimide ester; Cy5® NHS ester; NHS-Cy5; Cyanine5 succinimidyl ester
EINECS	Contact for details

Quality Control

Our Cyanine 5 NHS Ester is manufactured under strict quality controls to ensure high purity and consistent performance for critical research and diagnostic applications. Each batch is analyzed by HPLC, NMR, and mass spectrometry to confirm chemical identity and purity. A comprehensive Certificate of Analysis (COA) detailing purity (typically >95%), absorbance/fluorescence maxima, and functional performance is provided with every shipment.

Storage

Preserve in a tightly closed container, protected from light. Store desiccated at -20°C or below. This product is hygroscopic (moisture-sensitive) and light-sensitive. Allow the vial to equilibrate to room temperature in a desiccator before opening to minimize moisture uptake.

Specification

Item	Specification
Appearance	Dark blue to green solid or film
Identification (HPLC)	Retention time corresponds to reference standard
Identification (MS)	Consistent with molecular ion [M]+
Purity (HPLC)	≥ 95.0%
Absorption Maximum (λmax)	646 - 652 nm
Emission Maximum (λem)	662 - 668 nm
Extinction Coefficient (ε)	≥ 250,000 L·mol⁻¹·cm⁻¹
Solubility	Soluble in DMSO, DMF, acetonitrile
Water Content (KF)	≤ 1.0 %

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.