Sulforhodamine B is widely used in biological research as a fluorescent dye for staining cells and tissues. It is particularly valuable in cell viability assays, where it helps determine the number of living cells in a sample. The dye binds to proteins in cells, and its fluorescence intensity can be measured to assess cell proliferation or cytotoxicity. Additionally, it is employed in microscopy and flow cytometry to visualize and analyze cellular structures or populations. Its high stability and bright fluorescence make it a reliable tool for various experimental applications in molecular biology and biochemistry.