PEG2-Cl is widely used as a reactive intermediate in organic synthesis, particularly in the modification of biomolecules. It is commonly employed in the preparation of polyethylene glycol (PEG) derivatives, which are essential in bioconjugation processes. These derivatives are utilized to enhance the solubility, stability, and bioavailability of therapeutic proteins and peptides in pharmaceutical formulations. Additionally, PEG2-Cl plays a role in the development of drug delivery systems, where it helps in creating targeted and controlled-release mechanisms. Its application extends to the modification of surfaces and materials, improving their biocompatibility for medical devices and implants. In research, it is used to functionalize nanoparticles and polymers for various biomedical applications, including imaging and diagnostics.