Description

Fluorescein Isothiocyanate I Hydrochloride is a high-purity, reactive derivative of fluorescein widely used as a critical fluorescent labeling reagent. Its primary value lies in its ability to form stable thiourea bonds with primary amines, enabling the sensitive detection and analysis of proteins, antibodies, and other biomolecules. This compound is essential for researchers and manufacturers in the biotechnology, pharmaceutical, and diagnostic industries, particularly for applications in flow cytometry, immunofluorescence, and fluorescence microscopy.

Application

• Fluorescent Labeling of Proteins and Antibodies: Conjugation to primary amine groups (e.g., lysine residues) for detection and quantification.
• Flow Cytometry (FACS): Preparation of fluorescently-tagged antibodies and probes for cell sorting and analysis.
• Immunofluorescence Microscopy (IF/ICC): Labeling agents for visualizing cellular and subcellular structures.
• Diagnostic Assay Development: Key component in the manufacture of fluorescent immunoassays and biosensors.
• Bioconjugation and Probe Synthesis: Creating targeted fluorescent probes for in vitro and in vivo imaging studies.
• Life Science Research: A fundamental tool for protein tracking, receptor binding studies, and molecular interaction analysis.

Basic Information

Product Name	Fluorescein Isothiocyanate I Hydrochloride
CAS No.	63469-13-6
Molecular Formula	C21H12ClNO5S • HCl
Molecular Weight	478.30 g/mol (as hydrochloride)
Synonyms	FITC I Hydrochloride; Fluorescein 5(6)-Isothiocyanate Hydrochloride; 5(6)-FITC Hydrochloride; 5-Isothiocyanatofluorescein Hydrochloride; 6-Isothiocyanatofluorescein Hydrochloride; Isomer I of Fluorescein Isothiocyanate Hydrochloride; Reactive Fluorescein Derivative Hydrochloride
EINECS	Contact for details

Quality Control

Our Fluorescein Isothiocyanate I Hydrochloride is manufactured under strict quality systems to ensure batch-to-batch consistency and high performance for sensitive applications. Each lot undergoes comprehensive analytical testing, including HPLC for purity and isomer ratio, spectral analysis for identity confirmation, and tests for residual solvents and moisture. A Certificate of Analysis (COA) detailing all specifications is provided with every shipment to support your quality assurance and regulatory needs.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 2-8°C. This product 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	Orange-red to brown powder
Identification (IR)	Conforms to structure
Purity (HPLC)	≥ 95.0% (Isomer I)
Total FITC Isomers (HPLC)	≥ 98.0%
Water Content (KF)	≤ 5.0%
Fluorescence	Suitable for labeling
Solubility	Soluble in DMSO, DMF; sparingly soluble in water

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