Cyanine3 amine is widely used in fluorescence labeling for biological research and diagnostics. It is particularly valuable in labeling proteins, nucleic acids, and other biomolecules for imaging and detection purposes. Its bright fluorescence in the orange-red spectrum makes it ideal for use in fluorescence microscopy, flow cytometry, and in vivo imaging. Additionally, it is employed in the development of fluorescent probes and assays, enabling researchers to study molecular interactions, cellular processes, and disease mechanisms with high sensitivity and specificity. Its primary amine group allows for efficient conjugation to carboxyl- or aldehyde-containing target molecules, making it a versatile tool in biochemical and biomedical applications.