Calcofluor white: Tips for improving its use

Calcofluor White (CFW) is a fluorescent brightener or "whitening agent" that is widely used in the textile and paper industries. It binds to beta 1-3 and beta 1-4 polysaccharides, such as cellulose and chitin, and will fluoresce with a bluish/white color when exposed to ultraviolet (UV) radiation. Hageage and Harrington first described the use of CFW as a nonspecific stain for fungi in clinical specimens and since then, this and some other similar compounds have received considerable attention and use for this purpose. This brief article describes some of the uses and conflicting reports in the literature regarding this stain.