Acid fuchsin is made from basic fuchsin homologues by the addition of sulphonic groups. There are four of these compounds, each of which could have up to three sulphonic groups attached, making twelve possible chemicals. Although there may be slight differences in their properties they are all satisfactory. Commercial Acid fuchsin is probably a variable mixture.
It is used in the Van Gieson method in conjunction with picric acid to demonstrate collagen fibres red, and in Masson's trichrome to colour smooth muscle in contrast to collagen. It is less commonly used in a method for mitochondria.
R. D. Lillie.
Conn's Biological Stains
Williams & Wilkins, Baltimore, MD., U.S.A.
Edward Gurr, (1971)
Synthetic dyes in biology, medicine and chemistry
Academic Press, London, England.