amyloid bacteria biebrich scarlet cas registry number carbohydrate chemical formula congo red crystal disinfectant dye eosin y fast green fcf french academy of sciences fuchsine acid gentian violet giemsa stain gram staining haematoxylin hemosiderin iron leonhart fuchs light green sf yellowish lipid melting point methyl blue methyl violet methylene blue microbiology molar mass new fuchsine oil red o partition coefficient periodic acid-schiff stain phosphomolybdic acid prussian blue safranin schiff test silver stain simplified molecular input line entry specification solid solubility staining sudan black b sudan ii sudan iii sudan iv sudan stain sulfonic acid textile vapor pressure water