m-PEG7-NHS ester is widely used in bioconjugation and chemical modification processes. It serves as a linker to attach polyethylene glycol (PEG) chains to proteins, peptides, or other biomolecules, enhancing their solubility, stability, and biocompatibility. This modification is particularly valuable in drug delivery systems, where PEGylation reduces immunogenicity and prolongs the circulation time of therapeutic agents. Additionally, it is employed in surface functionalization of nanoparticles and materials for biomedical applications, improving their performance in targeted therapies and diagnostics. Its reactive NHS ester group ensures efficient coupling with amino groups, making it a versatile tool in bioconjugation chemistry.