Used in bioconjugation and drug delivery systems, it serves as a linker molecule to attach targeting ligands or therapeutic agents to biomolecules. Its endo-BCN group enables efficient click chemistry reactions, particularly with azide-containing compounds, facilitating precise and rapid conjugation. The PEG2 spacer enhances solubility and reduces steric hindrance, improving the stability and efficacy of the final conjugate. It is widely applied in the development of antibody-drug conjugates (ADCs), targeted cancer therapies, and diagnostic probes, offering controlled and site-specific modifications.