Is Eosin Y vegan?

Eosin Y

Vegan

Eosin Y is a synthetic fluorescent acidic dye of the xanthene class, produced by the action of bromine on fluorescein. It is widely used as a histological stain (paired with haematoxylin in H&E staining), binding to basic proteins and staining cytoplasmic structures dark red or pink.

Also known as Acid Red 87, Bromoeosine, Eosine Yellowish, Tetrabromofluorescein
CAS number 17372-87-1
CI number CI 45380
Last reviewed 3 June 2026

Sources

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