Azure A is formed by the oxidation of Methylene blue and is strongly metachromatic. It is used in making azure eosin stains for blood smear staining. Compare the formulae of the three azures and methylene blue.
R. D. Lillie.
Conn's Biological Stains
Williams & Wilkins, Baltimore, MD., U.S.A.
Aldrich chemical catalogue, 1992
Aldrich Chemical Company, Milwaukee, WI, USA.
Edward Gurr, (1971)
Synthetic dyes in biology, medicine and chemistry
Academic Press, London, England.
Susan Budavari, Editor, (1996)
The Merck Index, Ed. 12
Merck & Co., Inc., Whitehouse Station, NJ, USA