of infection. Rose bengal is used to suppress bacterial growth in several microbiological media, including Cooke's rose bengal agar. Rose bengal has been used as a protoplasm stain to discriminate between living and dead micro-organisms, particularly Foraminifera, since the 1950s when Bill Walton developed the technique. Rose bengal acetate can act as a photosensitiser and may have potential in photodynamic therapy to treat some cancers. References External links Absorption and extinction data Ophthalmology Triarylmethane dyes Phenols Chloroarenes Iodoarenes Spiro compounds VMAT inhibitors Acid dyes