Used primarily in bioconjugation and drug delivery systems, this compound serves as a versatile linker for attaching biomolecules, such as proteins or peptides, to other entities like nanoparticles or therapeutic agents. Its PEG (polyethylene glycol) spacer enhances solubility and reduces immunogenicity, making it suitable for in vivo applications. The SPDP (N-succinimidyl 3-(2-pyridyldithio)propionate) moiety enables the formation of disulfide bonds, allowing for controlled release of conjugated molecules in reducing environments, such as inside cells. This makes it valuable in targeted drug delivery, antibody-drug conjugates, and diagnostic assays where precise and stable linkage is required.