Boc-NH-PEG7-acetic acid is widely used in bioconjugation and pharmaceutical research due to its long, hydrophilic PEG spacer. The compound enables efficient coupling between biomolecules such as peptides, proteins, or antibodies and other functional groups, improving solubility and reducing aggregation. Its Boc-protected amine allows for controlled deprotection under mild acidic conditions, enabling stepwise synthesis in complex molecule assembly. The acetic acid terminus provides a handle for activation and attachment to amines via standard carbodiimide coupling chemistry. This makes it valuable in the development of PEGylated therapeutics, drug delivery systems, and diagnostic probes where enhanced pharmacokinetics and reduced immunogenicity are desired. It is also employed in the synthesis of linkers for antibody-drug conjugates (ADCs) and in surface functionalization of nanoparticles and biosensors.