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Molekula

Molekula

Eosin Y (C.I. 45380)

SKU 31787521 CAS 17372-87-1 C20H6Br4Na2O5 MW 691.85 In stock (5+ packs) — same-day dispatch Bulk quantities on request

Supplying 4,500+ customers in over 80 countries

ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need

Eosin Y (C.I. 45380) is a synthetic fluorescent dye belonging to the xanthene family, widely used as a biological stain in microscopy, histology, and microbiology for differentiating cellular structures. It is also employed as a colorant in cosmetics (as D&C Red No. 22), in ink production, and as a photosensitizer in photodynamic therapy. This chemical has a CAS number of 17372-87-1, a molecular formula of C20H6Br4Na2O5, and a molecular weight of 691.85. It should be stored at ambient conditions, with a signal word of Warning indicating moderate hazard. Molekula supplies Eosin Y from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

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Example image for illustration only. Other packaging and pack sizes are available.

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Pricing & pack sizes

Pack sizes & pricing

These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.

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  • 5 g — $20.90 per pack
  • 25 g — $41.20 per pack
  • 50 g — $72.20 per pack
  • 100 g — $96.90 per pack
  • 250 g — $153.90 per pack

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Prices exclude VAT/sales tax and shipping.

Specifications

Property Value
Appearance Rust red powder
Loss on Drying ≤ 5.0%
Dye Content ≥ 90.0%

Storage & handling

Property Value
Storage Temperature Ambient
Acidity Neutral

Literature values

Published physical properties of the substance, not batch specifications.

Property Value
Melting Point 300 °C (decomposes)

Source: PubChem CID 11048 (CAMEO Chemicals)

Identification

Property Value
SKU 31787521
CAS Number 17372-87-1
IUPAC Name disodium;2-(2,4,5,7-tetrabromo-3-oxido-6-oxoxanthen-9-yl)benzoate
EC Number 241-409-6
Molecular Formula C20H6Br4Na2O5
Molecular Weight 691.85
Exact Mass 691.6703
SMILES C1=CC=C(C(=C1)C2=C3C=C(C(=O)C(=C3OC4=C(C(=C(C=C24)Br)[O-])Br)Br)Br)C(=O)[O-].[Na+].[Na+]
InChIKey SEACYXSIPDVVMV-UHFFFAOYSA-L
InChI InChI=1S/C20H8Br4O5.2Na/c21-11-5-9-13(7-3-1-2-4-8(7)20(27)28)10-6-12(22)17(26)15(24)19(10)29-18(9)14(23)16(11)25;;/h1-6,25H,(H,27,28);;/q;2*+1/p-2
PubChem CID 11048
REACH Code Y110
TSCA Listed Yes
HTS Code 32129000
Tariff Code 3212900000

Safety & GHS

Warning
  • GHS pictogram — Health Hazard Health Hazard GHS07

Hazard statements

  • H303 May be harmful if swallowed
  • H317 May cause an allergic skin reaction
  • H319 Causes serious eye irritation

Precautionary statements

  • P261 Avoid breathing dust/fume/gas/mist/vapours/spray
  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P302+352 IF ON SKIN: Wash with soap and water
  • P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing

Documents

Certificate of Analysis (CoA) by batch

Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.

Synonyms

  • Acid red 87
  • Bromo acid
  • Eosin
  • Eosin yellowish
  • Eosin YS
  • Eosine
  • Eosine G
  • Eosine Y
  • Eosine Yellowish
  • Sodium eosine

Frequently asked questions

What is Eosin Y (C.I. 45380) commonly used for?

Eosin Y is primarily used as a fluorescent dye in biological and medical staining, microscopy, and as a photosensitizer in photodynamic therapy.

What is the chemical formula and molecular weight of Eosin Y?

The chemical formula is C₂₀H₆Br₄Na₂O₅, and the molecular weight is 691.85 g/mol.

How should Eosin Y be stored?

Store Eosin Y at ambient temperature in a cool, dry place, away from direct sunlight and incompatible substances.

What grades or purity levels of Eosin Y does Molekula supply?

Molekula supplies Eosin Y in analytical and reagent-grade purity, suitable for research and industrial applications.

Can Molekula supply Eosin Y in bulk quantities?

Yes, Molekula can provide Eosin Y in bulk, with quantities tailored to your specific requirements—please contact us for details.

What documentation comes with an order of Eosin Y?

Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and batch-specific documentation for traceability.

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