Biebrich Scarlet is a red dye that primarily stains cytoplasm and muscle fibers, while Acid Fuchsin is a red dye that stains connective tissue, particularly collagen. When used together, they create a contrast that allows for the differentiation of tissues under a microscope. This dual staining is particularly useful in distinguishing between muscle fibers, which take up the Biebrich Scarlet, and collagen, which takes up the Acid Fuchsin.
