Soluble in water (390g/L at 20C), and ethanol.
Eosin B sodium salt is a cell and tissue stain. Eosin B sodium salt is used as a counter stain for collagen, as a tissue stain for cell granules, nuclei, and microorganisms when coupled with Azure A (sc-203729), and as a stain for cell differentiation of the anterior pituitary.
Eosin B is used for estimating a wide range of proteins by the eosin B dye method. At acidic pH, eosin B binds to proteins and absorption of the protien-dye complex at 536–544 nm is proportional to the concentration of the proteins. Inorganic and organic acids are used for the assay, the optimum concentration of acid for each assay differs from acid to acid. The compound provides minimal interference with commonly used compounds in protein purification and biomolecules like DNA, RNA, lipids, carbohydrates and minerals which are generally present in biological fluids. It is used for estimating proteins in tissue homogenates, isolated proteins and various biological fluids.