Similar to other sulforhodamine dyes, the highly water-soluble sulforhodamine B can also be used as a polar tracer for the studies of cell morphology and neuronal cell-cell communication. In addition, sulforhodamine B has been shown to be a superior protein stain for use in the quantification of cellular proteins of cultured cells.The intensely colored, water soluble dye is particularly useful for in vitro cell-based screening of anticancer drugs. The dye is believed to bind to basic amino acids of cellular proteins. Thus, colorimetric measurement of the bound dye provides an estimate of the total protein mass that is related to the cell number. The assay method is simple and reproducible, and the end-point measurement is not time-critical, a significant advantage over assays using tetrazolium derivatives. The method is especially applicable to large scale screening of anticancer drug candidates from natural extracts or synthetic chemicals.
