Widely used as a fluorescent labeling reagent for amines and sulfhydryl groups in biochemical and analytical applications. Its high reactivity allows efficient tagging of peptides, proteins, and amino-containing small molecules for detection in fluorescence-based assays. Commonly applied in HPLC and capillary electrophoresis to enhance sensitivity of detection. Also utilized in cellular imaging due to its stability and strong fluorescence signal in aqueous environments. Suitable for both in vitro and ex vivo labeling, especially when tracking biomolecule interactions or metabolic pathways.