Eosin Y is a xanthene dye and is used for the differential staining of connective tissue and cytoplasm. In histopathology, it is applied as a counterstain after hematoxylin and before methylene blue. It is also used as a background stain, thereby giving contrast to the nuclear stains.||Synonyms:|Solvent Red 43; 2′,4′,5′,7′-Tetrabromofluorescein; Acid Red 87; Bromofluorescein; Bronze Bromo ES; Eosin yellowish||CAS No:|15086-94-9||Molecular Formula:|C20H8Br4O5||Molecular Weight:|647.89||Appearance:|Light orange powder||Purity:|≥96% (Dye content)||Solubility:|Clear orange-yellow solution with fluoresence (0.1% in Methanol)||Storage and Stability:|May be stored at RT.