Widely used in bioconjugation processes, this compound acts as a crosslinking agent to link proteins, peptides, or other biomolecules through primary amine groups. Its NHS ester groups react efficiently with amines under mild conditions, forming stable amide bonds. Commonly applied in the development of antibody-drug conjugates (ADCs), it enables controlled attachment of payloads to targeting molecules. It is also used in immobilizing biomolecules onto surfaces such as biosensors, microplates, or nanoparticles, where maintaining biological activity is critical. Due to the hydrophilic nature of the diglycolic acid spacer, it helps reduce aggregation and improves solubility in aqueous environments, making it suitable for applications in drug delivery, diagnostics, and protein labeling.