This compound is widely utilized in bioconjugation and chemical biology for the modification of biomolecules. Its aminooxy group enables selective reactions with aldehydes and ketones, making it valuable for labeling proteins, peptides, and other biomolecules. The PEG (polyethylene glycol) spacer enhances solubility and reduces steric hindrance, improving efficiency in conjugation processes. It is particularly useful in the development of antibody-drug conjugates (ADCs) and other therapeutic agents, where precise targeting and controlled release are critical. Additionally, it finds applications in surface functionalization for biosensors and nanomaterials, facilitating the attachment of biomolecules for analytical or diagnostic purposes. The t-butyl ester group provides stability during synthesis and can be cleaved to expose a carboxylic acid for further functionalization.