SPdp-PEG6-NHS ester is widely used in bioconjugation and protein modification applications. Its primary function is to link biomolecules, such as proteins or peptides, to other molecules or surfaces. The NHS ester group reacts efficiently with primary amines, enabling covalent attachment to target molecules, while the SPdp group allows for subsequent thiol-based conjugation. This makes it particularly useful in creating antibody-drug conjugates (ADCs), where precise and stable linkages are essential. Additionally, it is employed in the development of biosensors, drug delivery systems, and diagnostic tools, where controlled and specific binding is required. Its PEG6 spacer enhances solubility and reduces steric hindrance, improving the efficiency of the conjugation process.