This chemical is widely used in bioconjugation and protein modification due to its reactive sulfone group and PEG spacers. The sulfone group allows for selective coupling with thiol-containing molecules, making it ideal for creating stable thioether bonds in biological systems. The PEG4 spacers enhance solubility and reduce steric hindrance, improving the efficiency of conjugation reactions. It is commonly employed in antibody-drug conjugates (ADCs), where it links therapeutic agents to antibodies, ensuring targeted delivery of drugs to specific cells. Additionally, it is utilized in the development of bioconjugates for diagnostic imaging, enabling precise labeling of biomolecules. Its versatility also extends to surface modification of nanoparticles, enhancing their biocompatibility and stability for biomedical applications.