Histology, cytology and other related scientific disciplines study the microscopic anatomy of tissues and cells. In order to demonstrate a good tissue and cellular structure, the samples need to be stained in a correct manner. Phloxine B powder dye is used in various staining methods in microscopy. It is a component of Lendrum’s phloxine-tartrazine selective staining of viral inclusions and other dense structures. It is also used for staining keratin and mucin acc. to Kreyberg, and for staining nucleoli.