Used as a bifunctional linker in bioconjugation, particularly in the development of antibody-drug conjugates (ADCs) and targeted therapeutics. Its structure enables efficient coupling between biomolecules (like antibodies or peptides) and payloads (such as drugs or imaging agents) through stable amide bond formation. The extended PEG-like chain provides water solubility, reduces aggregation, and improves pharmacokinetics. The tetrazine group allows for rapid, bioorthogonal click chemistry with trans-cyclooctene (TCO)-modified compounds, enabling site-specific labeling or conjugation under physiological conditions. Commonly applied in radiopharmaceuticals, diagnostic probes, and precision medicine platforms where controlled, selective attachment is critical.