Molekula
Eosin B (C.I. 45400)
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 B (C.I. 45400) is a synthetic fluorescent dye belonging to the xanthene family, widely used in biology for staining tissues, microscopy, and as a tracer in flow cytometry. It is also applied as a histological counterstain, for example in place of Eosin Y in hematoxylin and eosin staining, and in some industrial dye formulations. Industrially, it serves as a colorant for dyeing and printing wool and cotton textiles and for coloring paper in pulp and paper processing. This chemical has a CAS number of 548-24-3, with the molecular formula C20H6Br2N2Na2O9 and a molecular weight of 624.06. It is stored at ambient conditions and classified with a signal word of "Danger" due to its hazardous properties. Molekula supplies Eosin B from research to bulk quantities with full documentation and ISO 9001:2015 traceability.
Example image for illustration only. Other packaging and pack sizes are available.
Pricing & pack sizes
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.
Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.
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10 g — £26.00 per pack ex VAT · £31.20 inc. VAT
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25 g — £30.90 per pack ex VAT · £37.08 inc. VAT
Need a different quantity or pack?
Tell us how much you need and when — drums, IBCs, sacks or a one-off bulk lot. We'll manufacture or source it and come back with a price.
Prices exclude VAT/sales tax and shipping.
Specifications
| Property | Value |
|---|---|
| Appearance | Brown to dark green powder |
| Loss on Drying | ≤ 10.0% |
| Solubility | Clear solution (0.1% aq.sol) |
| Dye Content | ≥85.0% |
| Absorptivity | ≥ 800 |
| Wavelength of Max. Absorption | 515.0-525.0nm |
| Suitability for Microscopy | Passes test |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Neutral |
Identification
| Property | Value |
|---|---|
| SKU | 48164504 |
| CAS Number | 548-24-3 |
| IUPAC Name | disodium;4',5'-dibromo-2',7'-dinitro-3-oxospiro[2-benzofuran-1,9'-xanthene]-3',6'-diolate |
| Molecular Formula | C20H6Br2N2Na2O9 |
| Molecular Weight | 624.06 |
| Exact Mass | 623.8215 |
| SMILES | C1=CC=C2C(=C1)C(=O)OC23C4=CC(=C(C(=C4OC5=C(C(=C(C=C35)[N+](=O)[O-])[O-])Br)Br)[O-])[N+](=O)[O-].[Na+].[Na+] |
| InChIKey | QGAYMQGSQUXCQO-UHFFFAOYSA-L |
| InChI | InChI=1S/C20H8Br2N2O9.2Na/c21-13-15(25)11(23(28)29)5-9-17(13)32-18-10(6-12(24(30)31)16(26)14(18)22)20(9)8-4-2-1-3-7(8)19(27)33-20;;/h1-6,25-26H;;/q;2*+1/p-2 |
| PubChem CID | 12961637 |
| REACH Code | Y110 |
| TSCA Listed | Yes |
| HTS Code | 3212.90.0050 |
| Tariff Code | 3212900000 |
Safety & GHS
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Corrosive
GHS05
Hazard statements
- H318 Causes serious eye damage
Precautionary statements
- P264 Wash thoroughly after handling
- P280 Wear protective gloves/protective clothing/eye protection/face protection
- P305+P351+P338 IF IN EYES: Rinse continuously with water for several minutes. Remove contact lenses if present and easy to do, continue rinsing
Documents
Safety Data Sheets (SDS)
Available in English, French, German, Italian, Portuguese, Spanish.
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 91
- Bluish, Eosine
- C.I. Acid Red 91
- Dibromodinitrofluorescein sodium
- Eosin BA
- Eosine BA
- Eosine BN
- Eosine BNX
- EOSINE I BLUISH
- Saffrosine
Frequently asked questions
What is Eosin B (C.I. 45400) commonly used for?
Eosin B is primarily used as a fluorescent dye in biological staining, microscopy, and as a pH indicator in analytical chemistry.
What is the chemical formula and molecular weight of Eosin B?
The formula is C₂₀H₆Br₂N₂Na₂O₉, and the molecular weight is 624.06 g/mol.
How should Eosin B be stored?
Store Eosin B at ambient temperature in a tightly sealed container, away from direct light and moisture.
What grades or purity levels of Eosin B does Molekula supply?
Molekula supplies analytical and reagent-grade Eosin B with specified purity levels—confirm exact grade upon inquiry.
Can Molekula supply Eosin B in bulk quantities?
Yes, Molekula can provide Eosin B in bulk; contact us for pricing and lead times based on your required volume.
What documentation comes with an order of Eosin B?
Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and batch-specific documentation.
Ready to order or need a custom pack?
Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.