This chemical is widely used in bioconjugation and labeling applications due to its reactive azido and 4-nitrophenyl carbonate groups. The azide group allows for click chemistry reactions, particularly with alkynes, enabling efficient and specific attachment of molecules such as proteins, peptides, or other biomolecules. The 4-nitrophenyl carbonate group is highly reactive towards amines, making it suitable for modifying amino-containing compounds like antibodies, enzymes, or polymers. It is often employed in the development of drug delivery systems, diagnostic probes, and functionalized biomaterials. Its water-soluble PEG4 spacer enhances solubility and reduces steric hindrance, ensuring effective conjugation in aqueous environments. This compound is particularly valuable in creating targeted therapeutics, biosensors, and advanced research tools in biochemistry and molecular biology.