Description

Fluorescein-Peg4-Acid CAS NO 1807518-76-8 is a high-purity, functionalized fluorescent dye derivative featuring a tetraethylene glycol (PEG4) spacer and a terminal carboxylic acid group. This molecular design is critical for creating stable, water-soluble conjugates with minimal impact on the biological activity of the target molecule. It is an essential building block for researchers and manufacturers in the life sciences sector who require precise labeling and detection capabilities. The compound enables the development of advanced diagnostic probes, imaging agents, and bioconjugation platforms.

Application

• Bioconjugation & Probe Development: The carboxylic acid group allows for covalent attachment to amines on proteins, antibodies, peptides, and nanoparticles via standard coupling chemistry (e.g., EDC/NHS).
• Fluorescent Labeling & Imaging: Used to label biomolecules for fluorescence microscopy (e.g., confocal, super-resolution), flow cytometry, and in vitro diagnostic (IVD) assays.
• Drug Delivery & Pharmaceutical Research: Serves as a traceable linker in the synthesis of antibody-drug conjugates (ADCs) and other targeted therapeutic constructs to study pharmacokinetics and biodistribution.
• Diagnostic Reagents: A key component in the formulation of fluorescent lateral flow assays, ELISA kits, and other clinical diagnostic tools.
• Material Science & Surface Modification: Employed to introduce fluorescent properties onto surfaces, polymers, and hydrogels for sensor development and biomaterial characterization.
• Cellular & Molecular Biology: Facilitates the study of cellular uptake, receptor binding, and intracellular trafficking pathways.

Basic Information

Product Name	Fluorescein-Peg4-Acid
CAS No.	1807518-76-8
Molecular Formula	C37H41NO13
Molecular Weight	707.73 g/mol
Synonyms	5-FAM-PEG4-acid; 5-Carboxyfluorescein-PEG4-acid; Fluorescein-5-PEG4-C2-acid; 6-FAM SE precursor-PEG4; 5(6)-Carboxyfluorescein tetraethylene glycol acetic acid; 5-FAM-PEG4-CH2CH2COOH; 5(6)-FAM, SE-PEG4-acid; 5-Isomer of Carboxyfluorescein tetraethyleneglycol ester
EINECS	Contact for details

Quality Control

Our Fluorescein-Peg4-Acid is manufactured under strict quality management systems. Each batch undergoes rigorous analytical testing, including HPLC for purity and isomer ratio confirmation, mass spectrometry (MS) for identity verification, and NMR for structural confirmation. We provide comprehensive Certificates of Analysis (COA) with each shipment, detailing all relevant specifications. Our quality commitment ensures batch-to-batch consistency for your critical research and development applications.

Storage

Preserve in a tightly closed container, protected from light. Store at -20°C or below under desiccant. This product is hygroscopic (moisture-sensitive) and light-sensitive. Allow the vial to warm to room temperature in a desiccator before opening to minimize moisture uptake. For long-term storage, keep the primary container in a sealed secondary container with a desiccant.

Specification

Item	Specification
Appearance	Orange to red solid
Identification (HPLC/MS)	Conforms to reference standard
Purity (HPLC)	≥ 95% (5-Isomer enriched)
Isomer Ratio (5-/6-)	≥ 90:10 (5-Isomer:6-Isomer)
Water Content (KF)	≤ 2.0%
Solubility	Soluble in DMSO, DMF; Slightly soluble in water

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