Description

Cyanine5 Carboxylic Acid 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 and diagnostics who require high-performance, stable fluorescent labels for advanced imaging and detection applications. Cyanine5 Carboxylic Acid CAS NO 1032678-07-1 offers a key building block for developing sensitive probes and assays.

Application

• Fluorescent Labeling of Biomolecules: Conjugation to antibodies, proteins, peptides, and oligonucleotides for use in immunofluorescence (IF), flow cytometry, and Western blotting.
• Bioimaging Probe Synthesis: A key precursor for developing targeted near-infrared (NIR) imaging agents used in in vitro and in vivo fluorescence microscopy and small animal imaging.
• Diagnostic Assay Development: Integration into lateral flow assays, ELISA kits, and other diagnostic platforms to provide a sensitive fluorescent readout.
• Polymer and Nanoparticle Functionalization: Modification of polymeric materials, dendrimers, and nanoparticles to create fluorescent carriers for drug delivery or tracking studies.
• Fluorescence Resonance Energy Transfer (FRET): Serving as an acceptor or donor dye in FRET-based molecular beacon and biosensor constructs.
• Cell and Tissue Staining: Preparation of custom fluorescent stains for visualizing cellular structures and processes with minimal background autofluorescence.

Basic Information

Product Name	Cyanine5 Carboxylic Acid
CAS No.	1032678-07-1
Molecular Formula	C37H43N2O2+
Molecular Weight	547.75 g/mol (for cation)
Synonyms	Cy5 Carboxylic Acid; Cy5-COOH; Sulfo-Cyanine5 carboxylic acid (common trade form); 1-(5-Carboxypentyl)-2-((1E,3E)-3-(1-(5-carboxypentyl)-3,3-dimethyl-5-sulfoindolin-2-ylidene)prop-1-en-1-yl)-3,3-dimethyl-3H-indol-1-ium-5-sulfonate; Cy5 NHS ester precursor; Near-IR fluorescent dye acid; Carboxycyanine5; Reactive Cy5 dye
EINECS	Contact for details

Quality Control

Our Cyanine5 Carboxylic Acid is manufactured under strict quality systems to ensure batch-to-batch consistency and high performance in sensitive applications. Each lot undergoes comprehensive analytical testing, including HPLC for purity and spectrophotometric analysis to verify absorbance/fluorescence profiles. A detailed Certificate of Analysis (COA) documenting identity, purity, and other critical parameters is provided with every shipment to support your quality assurance protocols.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at -20°C or below for long-term stability. This compound is hygroscopic (moisture-sensitive) and light-sensitive. Allow the vial to equilibrate to room temperature in a desiccator before opening to prevent condensation and moisture uptake.

Specification

Item	Specification
Appearance	Dark blue to green solid
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	662 - 668 nm
Extinction Coefficient (ε)	≥ 250,000 L·mol⁻¹·cm⁻¹
Water Content (KF)	≤ 5.0%

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