Widely used as a fluorescent labeling reagent, particularly for amines and sulfhydryl groups in biomolecules. Its high fluorescence quantum yield and sensitivity make it ideal for detecting proteins, peptides, and nucleic acids in biochemical assays. Commonly applied in fluorescence microscopy, flow cytometry, and electrophoresis due to its strong signal and photostability. Also employed in the development of fluorescent probes for cellular imaging, where it helps track molecular interactions and localization in live or fixed cells. Its reactivity with primary amines allows for conjugation in labeling kits and diagnostic reagents.