Widely used in bioconjugation and drug delivery systems, it serves as a linker to improve solubility and stability of therapeutic compounds. Its hydrophilic PEG chains enhance biocompatibility and reduce immunogenicity, making it ideal for targeted drug delivery and protein modification. Additionally, it is employed in the development of antibody-drug conjugates (ADCs) and peptide-based therapeutics to optimize pharmacokinetics and bioavailability. It also finds applications in nanotechnology for surface modification of nanoparticles to prolong circulation time in vivo.