Used in bioconjugation and drug delivery systems, it serves as a linker to connect biomolecules or drugs to carriers, enhancing solubility and stability. It is particularly valuable in the development of antibody-drug conjugates (ADCs) and targeted therapies, where it facilitates controlled release and improved targeting efficiency. Additionally, it is employed in the modification of peptides, proteins, and nanoparticles for research and therapeutic applications. Its hydrophilic PEG spacer helps reduce immunogenicity and prolong circulation time in biological systems.