DBCO-PEG4-C2-acid is widely utilized in bioconjugation and click chemistry applications due to its reactive DBCO (dibenzocyclooctyne) group, which enables efficient and selective coupling with azide-containing molecules. Its PEG4 spacer enhances solubility and flexibility, making it suitable for modifying biomolecules like proteins, peptides, and antibodies without compromising their functionality. This compound is particularly valuable in drug delivery systems, where it facilitates the targeted attachment of therapeutic agents to carriers or biomolecules. Additionally, it is employed in the development of diagnostic probes and imaging agents, enabling precise labeling and tracking of biological targets in research and clinical settings. Its acid group allows for further functionalization or conjugation to surfaces, expanding its utility in material science and nanotechnology.