m-PEG4-Boc is widely used in bioconjugation and drug delivery systems due to its ability to modify biomolecules while providing solubility and stability. It serves as a protective group for amines during peptide synthesis, allowing selective deprotection under mild acidic conditions. The PEG (polyethylene glycol) spacer enhances water solubility and reduces immunogenicity, making it valuable in the development of therapeutic proteins and peptides. Additionally, it is employed in the creation of prodrugs, where the Boc group can be cleaved to release the active drug in targeted environments. Its applications also extend to materials science, where it is used to functionalize surfaces or nanoparticles for biomedical research.