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CAS 1 record

CAS 81-88-9

CAS 81-88-9 matches 1 EU annex record across Annex II–VI of Regulation 1223/2009.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 81-88-9
CAS 81-88-9PubChem CID 6694

Rhodamine B

Rhodamine B is an organic chloride salt having N-[9-(2-carboxyphenyl)-6-(diethylamino)-3H-xanthen-3-ylidene]-N-ethylethanaminium as the counterion. An amphoteric dye commonly used as a fluorochrome. It has a role as a fluorescent probe, a fluorochrome and a histological dye. It is an organic chloride salt and a xanthene dye. It contains a rhodamine B(1+). — ChEBI

IUPAC name
[9-(2-carboxyphenyl)-6-(diethylamino)xanthen-3-ylidene]-diethylazanium chloride
Molecular formula
C28H31ClN2O3
Molecular weight
479.0 g/mol
Exact mass
478.2023205 Da
Topological polar surface area
52.8 Ų
Hydrogen-bond donors
1
Hydrogen-bond acceptors
5
Covalent units
2
Defined stereocentres
0

Also known as

Basic Violet 10Brilliant Pink BTetraethylrhodamineRhodamine B chlorideCalcozine Red BXSymulex Magenta FRhodamineRhodamine O
16 more reported names
Rheonine BRhodamine FBGeranium lake NRhodamine BARhodamine BFRhodamine BLRhodamine BNRhodamine BSRhodamine BXRhodamine BXLRhodamine BXPBasic Rose RedRhodamine Lake Red BSymulex Pink FADC Rhodamine BEdicol Suppa Rose BS
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External database identifiers

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Records for CAS 81-88-9

1 total
No records found for this CAS number.

How CAS 81-88-9 is used on this site

CAS 81-88-9 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 1 EU annex record shares this identifier, which helps you cross-check whether the same substance appears under one regulatory context or several.

Use this page when a supplier specification, SDS or raw-material dossier gives you CAS 81-88-9 and you need to see every linked Annex II–VI record in one place. The entry cards above are the quickest route to concentration limits, warnings, annex placement and product-type conditions.