Acid Fuchsine 1 % (MASSON A)

Acid fuchsin 1 % (Masson A) is a staining solution used as an ingredient in Masson trichrome staining. Acid fuchsin is a synthetic acid dye present in a 1% aqueous solution. In Masson trichrome staining, it is used to stain cytoplasmic structures, muscle tissue, and erythrocytes.

Masson trichrome staining is a multistep staining method commonly used to examine connective tissue, muscle, and other tissue components in histological specimens. It consists of several steps, with acid fuchsin as the first stain applied to the tissue. Subsequent staining with other dyes, such as aniline blue or light green, results in a differentiated image of the various tissue components, with collagen fibers, smooth muscle, erythrocytes, and cytoplasmic structures stained differently.