Sulforhodamine B

Sulforhodamine B (free acid) is a xanthene dye widely used in cell biology, analytical chemistry, and histology as a sensitive fluorescent and colorimetric tracer. With strong absorption in the visible range (~565 nm) and intense red emission (~586 nm), it is employed in fluorescence microscopy, flow cytometry, and microplate assays, as well as in cell proliferation and cytotoxicity studies (notably the SRB assay for total cellular protein content). In addition, it is used as a pH indicator, tracer in environmental and hydrological studies. Its stability, high molar absorptivity, and photophysical properties make it a robust, inexpensive, and widely adopted labeling and detection reagent. Spectral Data: lambdaEx=560nm, lambdaEm=580nm.