This compound is widely used in bioconjugation and click chemistry applications due to its reactive NHS ester and DBCO groups. The NHS ester allows for efficient coupling with primary amines, enabling the attachment of the molecule to proteins, peptides, or other amine-containing biomolecules. Meanwhile, the DBCO group facilitates strain-promoted azide-alkyne cycloaddition (SPAAC), a copper-free click chemistry reaction, which is particularly useful in biological systems where copper toxicity is a concern. This dual functionality makes it a valuable tool for labeling, crosslinking, or modifying biomolecules in research, diagnostics, and drug delivery systems. Its PEG spacer enhances solubility and reduces steric hindrance, improving reaction efficiency.