Eosin Y

CAS 15086-94-9C20H8Br4O5Cell Biology

Eosin Y (CAS: 15086-94-9), a tetrabrominated derivative of fluorescein, presents as a vibrant red crystalline powder. With the molecular formula C20H8Br4O5 and a molecular weight of 647.89 g/mol, it is an important acidic dye widely employed in histology and cell biology for differential staining. Its vivid colour and staining properties make it indispensable for visualizing cellular structures in microscopic preparations.

IUPAC: 2′,4′,5′,7′-Tetrabromofluorescein,Acid Red 87,Bromo acid J. TS, XL, or XX,Bromofluorescein,Bronze Bromo ES,Eosin yellowish,Solvent red 43
Synonyms: 2′,4′,5′,7′-TetrabromofluoresceinAcid Red 87Bromo acid J. TS, XL, or XXBromofluoresceinBronze Bromo ESEosin yellowishSolvent red 43

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Eosin Y (C20H8Br4O5) — chemical structure, CAS 15086-94-9; Life Science, fine chemical supplied by Tech Serve Solutions

Cell BiologyHematology and HistologyStains & DyesA to ZStains and Dyes

01 /Applications

Histology Staining

Eosin Y is a fundamental counterstain in H&E (Haematoxylin and Eosin) staining, providing bright pink to red coloration to cytoplasm, collagen, and other extracellular materials. This aids in the differentiation of tissue components.

Cytology Applications

In cytological preparations, Eosin Y is used to stain various cellular elements, enhancing contrast and aiding in the identification of cellular morphology. It is particularly useful for routine screening of smears.

Biological Stains

As part of the 'E-F' category of stains, Eosin Y functions as an acidic dye, binding to basic components of cells and tissues, such as positively charged proteins in the cytoplasm.

02 /Properties

Molecular weight	647.89
Empirical formula	C20H8Br4O5
Solubility	ethanol: soluble1 mg/mL

03 /Safety & handling

Protective equipment	Eyeshields, Gloves, type N95 (US), type P1 (EN143) respirator filter
Water hazard class (WGK, DE)	3

Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.

04 /Identifiers & registry

CAS number

15086-94-9

MDL number

MFCD00036189

PubChem substance

24853789

05 /Additional specifications

Colour Index Number	45380:2

06 /Quality & supply

Documentation

Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.

Supply & logistics

Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.

07 /Frequently asked questions

What is Eosin Y used for?

Eosin Y is primarily used as a counterstain in histology and cytology for visualizing cellular structures and tissue components under microscopy, particularly in H&E staining protocols.

What are the CAS number and chemical formula for Eosin Y?

The CAS number for Eosin Y is 15086-94-9, and its empirical formula is C20H8Br4O5.

What grade and purity does Tech Serve Solutions supply for Eosin Y?

Tech Serve Solutions supplies Eosin Y with a Colour Index Number of 45380:2. We do not represent this product as USP, BP, EP, or any pharmacopoeia grade; it is suitable for research and technical applications.

What are the safety precautions when handling Eosin Y?

When handling Eosin Y, it is essential to wear eyeshields and gloves. A type N95 (US) or type P1 (EN143) respirator filter should be used if airborne dust is generated. Handle with appropriate personal protective equipment and in a well-ventilated area.

How is Eosin Y packed and shipped?

Eosin Y is carefully packed to ensure safe transit and is exported globally by Tech Serve Solutions, adhering to all relevant shipping regulations for chemical substances.