Used as a key reagent in organic synthesis, particularly in the modification of biomolecules and polymers. It serves as a versatile linker or spacer in drug delivery systems, enabling the attachment of therapeutic agents to carriers for targeted delivery. Its bromine group allows for further functionalization, making it valuable in the development of prodrugs and bioconjugates. Additionally, it is employed in the preparation of hydrogels and other biocompatible materials for biomedical applications, such as tissue engineering and controlled release systems. The PEG (polyethylene glycol) chain enhances solubility and reduces immunogenicity, improving the pharmacokinetic properties of the final compounds.