Used extensively in bioconjugation and peptide synthesis, it serves as a linker to attach polyethylene glycol (PEG) chains to biomolecules. This modification enhances the solubility, stability, and bioavailability of therapeutic proteins, peptides, and other bioactive molecules. It is particularly valuable in drug delivery systems, where PEGylation reduces immunogenicity and prolongs circulation time in the body. Additionally, it is employed in the development of targeted therapies, enabling the precise attachment of functional groups for specific interactions with cellular targets. Its NHS ester groups facilitate efficient coupling with amine-containing compounds, making it a versatile tool in bioconjugation chemistry.