This chemical is widely used in bioconjugation and chemical biology research. It serves as a linker or spacer in the synthesis of protein conjugates, enabling the attachment of biomolecules to other entities like drugs, dyes, or solid supports. Its aminooxy group reacts selectively with aldehydes or ketones, forming stable oxime bonds, which is particularly useful in site-specific labeling of proteins or antibodies. The PEG3 spacer enhances solubility and reduces steric hindrance, improving the efficiency of conjugation reactions. It is also employed in the development of targeted drug delivery systems, where it helps link therapeutic agents to targeting molecules. Additionally, it finds applications in surface modification and the creation of functionalized materials for diagnostic assays.