This chemical is widely used in bioconjugation and labeling applications due to its unique properties. It is particularly valuable in the development of fluorescent probes for imaging and tracking biological molecules in live cells or tissues. The Cy3 fluorophore provides strong fluorescence, enabling high-sensitivity detection, while the PEG4 spacers enhance solubility and reduce steric hindrance during conjugation. The azide group allows for click chemistry reactions, facilitating efficient and specific attachment to target molecules. This makes it ideal for studying protein-protein interactions, cellular processes, and drug delivery systems. Additionally, its dual PEGylation improves biocompatibility, making it suitable for in vivo applications.