Widely used as a fluorescent dye in biological research, particularly in labeling and tracking biomolecules. It is commonly applied in fluorescence microscopy, flow cytometry, and immunofluorescence assays to visualize cellular structures and processes. Its bright fluorescence and photostability make it suitable for single-molecule imaging and live-cell studies. Additionally, it is utilized in the development of fluorescent probes and sensors for detecting specific ions or molecules in biological systems. It is also employed in nucleic acid labeling for techniques like fluorescence in situ hybridization (FISH) to study gene expression and chromosomal abnormalities. Its compatibility with various conjugation chemistries allows it to be attached to proteins, peptides, and antibodies for targeted imaging applications.