Widely used as a fluorescent derivatization agent for detecting primary amines in high-performance liquid chromatography (HPLC). It reacts rapidly with amino acids, peptides, and proteins under mild conditions, forming highly fluorescent isoindole derivatives that allow for sensitive detection at low concentrations. Commonly applied in pharmaceutical analysis, clinical diagnostics, and quality control of biopharmaceuticals. Also employed in hygiene monitoring systems to detect trace protein residues on surfaces, ensuring proper sanitation in medical and food processing environments. Its fast reaction kinetics and high sensitivity make it preferable over other reagents like fluorescamine in automated systems.