This bifunctional chemical, featuring an amino group at one end and a carboxylic acid group at the other connected by a hexaethylene glycol (PEG6) chain, is primarily used in bioconjugation and drug delivery. The multiple ethylene oxide units provide high water solubility, ideal for creating soluble conjugates. It serves as a versatile linker to connect drugs, proteins, or biomolecules, with the amino and carboxylic acid groups enabling easy attachment to various functional groups, thereby enhancing stability, bioavailability, and targeting. Its applications are especially prominent in antibody-drug conjugates (ADCs) and advanced therapeutic systems.