Propargyl-peg4-sulfone-peg4-t-butyl ester is primarily utilized in bioconjugation and click chemistry applications. Its propargyl group enables efficient and selective reactions with azides via copper-catalyzed azide-alkyne cycloaddition (CuAAC), making it valuable for labeling biomolecules such as proteins, peptides, and nucleic acids. The PEG4 spacers enhance solubility and reduce steric hindrance, improving reaction efficiency in aqueous environments. This compound is also employed in the development of drug delivery systems, where its sulfone group can act as a linker for controlled release mechanisms. Additionally, it finds use in material science for surface functionalization and the creation of biofunctionalized polymers. The t-butyl ester group provides stability during synthesis and can be selectively deprotected for further modifications.