Cy7 is widely used in biomedical research as a near-infrared fluorescent dye. Its applications include in vivo imaging, where it helps track cells, proteins, and other biomolecules due to its deep tissue penetration and minimal background interference. It is also employed in fluorescence microscopy and flow cytometry for labeling and detecting specific targets. Additionally, Cy7 is utilized in molecular probes and diagnostic assays for studying biological processes and disease mechanisms. Its stability and brightness make it a valuable tool in drug development and cancer research, particularly for tumor imaging and monitoring therapeutic responses.