Used primarily as a fluorescent probe in biochemical and analytical applications, this compound reacts with amino groups to form stable sulfonamide derivatives, enabling the detection and quantification of proteins and peptides. It is especially valuable in fluorescence spectroscopy and microscopy due to its strong emission upon binding to target molecules. Commonly employed in enzyme activity assays, it helps monitor conformational changes or ligand binding in real time. Its sulfonyl chloride group allows selective labeling of primary amines, making it useful in developing diagnostic reagents and studying biomolecular interactions.