Description

Cyanine5 Carboxylic Acid CAS NO 766503-38-2 is a reactive near-infrared fluorescent dye derivative, essential for creating custom bioconjugates. Its carboxylic acid functional group allows for straightforward covalent attachment to biomolecules like antibodies, peptides, and proteins via amine coupling. This product is critical for researchers and manufacturers in life sciences, diagnostics, and pharmaceutical development who require high-performance labeling reagents for advanced imaging, flow cytometry, and in vivo studies.

Application

• Bioconjugation and Probe Synthesis: Primary use for labeling antibodies, proteins, peptides, and oligonucleotides to create fluorescent probes.
• Bioimaging and Diagnostics: Enables the development of sensitive assays for fluorescence microscopy, in vivo imaging, and diagnostic test kits.
• Flow Cytometry: Used to synthesize fluorescent tags for cell surface marker detection and intracellular staining.
• Pharmaceutical Research: Critical in drug discovery for target identification, biodistribution studies, and pharmacokinetic analysis using labeled compounds.
• Material Science: Can be incorporated into polymers or nanoparticles to create functional, fluorescent materials for sensing applications.

Basic Information

Product Name	Cyanine5 Carboxylic Acid
CAS No.	766503-38-2
Molecular Formula	C37H45N2O2+
Molecular Weight	549.77 g/mol
Synonyms	Cy5 Carboxylic Acid; Cy5-COOH; Sulfo-Cyanine5 carboxylic acid (common trade variant); 1-(5-Carboxypentyl)-2-((1E,3E)-3-(1,1-dimethyl-3-(4-sulfobutyl)-1,3-dihydro-2H-benzo[e]indol-2-ylidene)prop-1-en-1-yl)-3,3-dimethyl-3H-indol-1-ium; Cy5 NHS ester precursor; Near-IR fluorescent dye acid; Benz[e]indolium dye derivative
EINECS	Contact for details

Quality Control

Our Cyanine5 Carboxylic Acid is produced under strict quality management systems. Each batch undergoes comprehensive analytical testing, including HPLC for purity, NMR and mass spectrometry for structural confirmation, and spectrophotometry to verify optical properties. A Certificate of Analysis (COA) detailing all specifications is provided with every shipment to ensure traceability and compliance with your research or manufacturing requirements.

Storage

Preserve in a tightly closed container, protected from light. Store at -20°C or below under desiccant. This compound is hygroscopic (moisture-sensitive) and light-sensitive. For long-term stability, store the product under an inert atmosphere. Allow the sealed vial to equilibrate to room temperature before opening to prevent condensation.

Specification

Item	Specification
Appearance	Dark blue to purple solid
Identification (HPLC)	Conforms to reference standard
Identification (NMR)	Conforms to structure
Purity (HPLC)	≥ 95.0%
Absorption (λmax)	646 - 652 nm
Emission (λmax)	662 - 668 nm
Extinction Coefficient (ε)	≥ 250,000 L·mol⁻¹·cm⁻¹
Water Content (KF)	≤ 2.0%

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