Used extensively in bioimaging and molecular labeling due to its strong fluorescence in the near-infrared range. It is commonly conjugated to antibodies, peptides, or nucleic acids for detection in techniques like fluorescence microscopy, flow cytometry, and Western blotting. Its carboxylic acid group allows easy coupling to amine-containing molecules using standard crosslinking chemistry such as EDC or NHS activation. Frequently employed in multiplex assays where distinct fluorescent signals are needed, enabling simultaneous tracking of multiple biological targets. Also utilized in in vivo imaging studies because of its favorable tissue penetration and low autofluorescence in the NIR window.