This compound is widely used as a fluorescent dye in various biological and chemical research applications. It is particularly valuable in labeling biomolecules such as proteins, peptides, and nucleic acids due to its bright fluorescence and stability. In fluorescence microscopy, it helps visualize cellular structures and track molecular interactions. Additionally, it is employed in fluorescence resonance energy transfer (FRET) studies to investigate molecular dynamics and distances. Its reactive SE (succinimidyl ester) group allows for efficient conjugation with amine-containing molecules, making it a versatile tool in biochemical assays and diagnostic applications.