Eosin Y disodium salt is used in combination with Azure II to show morphological details of marrow cells; buffered Azure A/Eosin Y method for demostrating cell granules, microorganisms and nuclei; for showing insect musculature; for demonstrating cells infected with mosquito-iridescent virus; use in combination with Alum Hematoxylin/Azure II to show mast cells, early necrobiotic changes in cells and protozoans, rickettsias and bacteria in tissues; to demonstrate volutin granules in any microorganism; Bond's modification of Mann's Eosin-Methyl Blue for Negri bodies in smears; Harris stain for Negri bodies in smears; Mann's method for staining Negri bodies in sections; Gridley's stain for Endamoeba in tissue sections; a modified methenamine-silver nitrate method for the demonstration of Endamoeba in sections. It is used as a counterstain for hematoxylin.
Eosin Y, a red xanthene dye, has been noted to reduce the affinity of Mg2+- ATPase for ATP and increase the enzyme affinity for Mg2+ at concentrations of 10-50 μM. At higher concentrations near 100 μM the affinity for Mg2+- ATPase for the ion-activator has been shown to be reduced. This compound has also been reported to be a photosensitizer that works as a molecular photoelectrode via catalyzation of the visible-light-driven electron-transfer reaction. This agent also enhances fluorescent quenching abilities by forming a complex with polyvinulpyrrolidone.
