PEG6-Tos is widely used as a versatile reagent in organic synthesis, particularly in the modification of biomolecules. Its primary application is in the protection and activation of hydroxyl groups, enabling the controlled attachment of polyethylene glycol (PEG) chains to target molecules. This process, known as PEGylation, is crucial in the pharmaceutical industry for enhancing the solubility, stability, and bioavailability of therapeutic proteins and peptides. Additionally, PEG6-Tos is employed in the development of drug delivery systems, where it helps in creating biocompatible and long-circulating nanoparticles. Its use in bioconjugation strategies also facilitates the creation of stable and functionalized surfaces for biosensors and diagnostic tools. Overall, PEG6-Tos plays a key role in improving the efficacy and performance of various biomedical applications.