Used in biochemical research for labeling peptides and proteins due to its fluorescent properties. The dansyl group provides strong fluorescence upon excitation, making it useful in studying molecular interactions, conformational changes, and enzyme activity. Commonly employed in assays involving proteases or peptidases where aspartic acid is part of the recognition sequence. Its fluorescence enhancement in hydrophobic environments allows detection of binding events or structural shifts in biomolecules. Also applied in chromatography as a derivatizing agent to improve detection sensitivity of amino acids and peptides.