Description

n-(m-Peg4)-N'-(Peg2-Nhs Ester)-Cy5 is a bifunctional, water-soluble cyanine dye derivative engineered for advanced bioconjugation and labeling applications. This compound matters because it combines the deep-red fluorescence of the Cy5 chromophore with a hydrophilic polyethylene glycol (PEG) spacer and an amine-reactive N-hydroxysuccinimide (NHS) ester, enabling stable, site-specific labeling of biomolecules with minimal aggregation. Researchers and developers in the fields of biopharmaceuticals, in vitro diagnostics (IVD), and life science research need it to create highly specific fluorescent probes, antibody-drug conjugates (ADCs), and sensitive assay reagents.

Application

• Fluorescent Labeling of Proteins and Antibodies: Site-specific conjugation via the NHS ester group to primary amines (e.g., lysine residues) for flow cytometry, immunofluorescence, and Western blotting.
• Antibody-Drug Conjugate (ADC) Linker-Payload Synthesis: Serves as a fluorescent tracer or as part of the linker-payload construct in ADC development and pharmacokinetic studies.
• Nucleic Acid Probe and Oligonucleotide Labeling: Conjugation to amine-modified oligonucleotides for fluorescence in situ hybridization (FISH) and real-time PCR applications.
• Polymer and Nanoparticle Functionalization: Incorporation into polymeric materials, dendrimers, or nanoparticle surfaces to impart fluorescence for tracking and imaging.
• In Vitro Diagnostic (IVD) Reagent Development: Manufacturing of fluorescent conjugates for clinical assay kits, including lateral flow assays and microarrays.
• Live-Cell and In Vivo Imaging Probes: Creation of targeted imaging agents due to the near-infrared fluorescence of Cy5, which offers deeper tissue penetration and reduced background autofluorescence.

Basic Information

Product Name	n-(m-Peg4)-N'-(Peg2-Nhs Ester)-Cy5
CAS No.	2107273-28-7
Molecular Formula	Contact for details
Molecular Weight	Contact for details
Synonyms	Cy5-PEG4-NHS ester; Cyanine5-PEG4-NHS; m-PEG4-Cy5-NHS ester; 1-(3-{2-[2-(2-{2-[(1E,3E,5E)-5-(1-{6-[(2,5-dioxopyrrolidin-1-yl)oxy]-6-oxohexyl}-3,3-dimethyl-5-sulfo-1,3-dihydro-2H-indol-2-ylidene)penta-1,3-dien-1-yl]-3,3-dimethyl-5-sulfo-1H-indol-1-yl)ethoxy]ethoxy}ethoxy)propyl)-1H-pyrrole-2,5-dione; NHS-PEG4-Cy5; PEGylated Cy5 NHS ester; Amine-reactive Cy5-PEG4
EINECS	Contact for details

Quality Control

Our n-(m-Peg4)-N'-(Peg2-Nhs Ester)-Cy5 is manufactured under strict quality management systems. Each batch undergoes rigorous analytical testing, including HPLC for purity assessment, NMR and mass spectrometry for structural confirmation, and spectrophotometry to verify absorbance and fluorescence properties. Certificates of Analysis (COA) detailing batch-specific results are available upon request to ensure traceability and compliance with your research or production standards.

Storage

Preserve in a tightly closed container, protected from light. Store desiccated at -20°C or below. This compound is hygroscopic (moisture-sensitive) and strictly light-sensitive (protect from all light exposure). Allow the vial to equilibrate to room temperature in a desiccator before opening to minimize moisture uptake. For long-term storage, consider under an inert atmosphere.

Specification

Item	Specification
Appearance	Dark blue to purple solid
Identification (HPLC)	Retention time corresponds to reference standard
Identification (NMR)	Spectrum consistent with structure
Purity (HPLC)	≥ 95%
Absorption Maximum (λmax)	~649 nm ± 3 nm
Emission Maximum	~670 nm ± 3 nm
Extinction Coefficient (ε)	Contact for details
Moisture Content (KF)	≤ 2.0%
Solubility	Soluble in DMSO, DMF, water

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