Description

Cy5.5 Acid(Mono So3) is a near-infrared fluorescent dye derivative functionalized with a carboxylic acid group and a single sulfonate moiety. This compound is essential for creating stable, water-soluble conjugates with biomolecules due to its excellent solubility and minimal non-specific binding. It is primarily needed by researchers and manufacturers in the biotechnology, pharmaceutical, and in vivo imaging sectors for advanced diagnostic and therapeutic applications.

Application

• Bioconjugation and Probe Labeling: Covalent attachment to antibodies, peptides, proteins, and oligonucleotides for fluorescence-based assays.
• In Vivo Imaging: Used as a contrast agent in preclinical small animal imaging studies due to its deep tissue penetration and low autofluorescence.
• Diagnostic Kit Development: Key component in the formulation of lateral flow assays (LFAs), ELISA kits, and other immunoassay platforms.
• Flow Cytometry: Labeling of cell surface markers for high-sensitivity detection in multicolor flow cytometry panels.
• Fluorescence Microscopy: Staining of cellular structures and tracking of biological processes in fixed and live cells.
• Drug Delivery Research: Conjugation to nanoparticles, liposomes, or polymer carriers to track biodistribution and pharmacokinetics.

Basic Information

Product Name	Cy5.5 Acid(Mono So3)
CAS No.	251102-88-2
Molecular Formula	C37H45N3O7S2- • Counterion+
Molecular Weight	Contact for details
Synonyms	Sulfo-Cyanine5.5 carboxylic acid; Cy5.5 Mono-sulfonated Acid; 1H-Benz[e]indolium, 2-[5-[1-carboxy-4-(1,3-dihydro-3,3-dimethyl-1-(4-sulfobutyl)-2H-benz[e]indol-2-ylidene)-1,3-butadienyl]-2-thienyl]-3,3-dimethyl-1-(4-sulfobutyl)-, inner salt; Cy5.5™-Acid (Mono So3); Sulfo-Cy5.5 NHS ester precursor; Near-IR fluorescent dye acid; CAS 251102-88-2
EINECS	Contact for details

Quality Control

Our Cy5.5 Acid(Mono So3) is produced under strict quality management systems. Each batch undergoes rigorous analytical testing to ensure high purity, consistent performance, and batch-to-batch reproducibility for sensitive research and diagnostic applications. Certificates of Analysis (COA) with detailed HPLC purity, absorbance, and fluorescence data are provided with every shipment.

Storage

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

Specification

Item	Specification
Appearance	Dark blue to green solid
Identification (HPLC/UV-Vis)	Conforms
Purity (HPLC)	≥ 95.0%
Absorption Maximum (λmax)	~683 nm
Emission Maximum (λem)	~703 nm
Extinction Coefficient (ε)	Contact for details
Water Content (KF)	≤ 5.0%
Single Spot on TLC	Conforms

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