Maleimide-PEG₁₂-NHS ester (CAS 1426151-00-9)

Maleimide-PEG12-NHS ester is a chemical compound widely utilized in the field of bioconjugation, a key technique in biochemical and molecular biology research. This compound combines three functional groups: maleimide, polyethylene glycol (PEG) of 12 units in length (PEG12), and N-hydroxysuccinimide (NHS) ester, each providing specific functionalities that are crucial for its applications in creating stable bioconjugates. The NHS ester group in Maleimide-PEG12-NHS ester facilitates efficient conjugation to primary amines, typically found on lysine residues within proteins or at the N-termini of peptides. This reaction forms stable amide bonds, allowing for the covalent attachment of the rest of the molecule to biomolecules. This feature is particularly valuable for modifying proteins or other amine-containing biomolecules under physiological conditions. Maleimide is a highly reactive group towards thiol groups, such as those found in cysteine residues of proteins. This selectivity is instrumental in forming thioether bonds with sulfhydryl groups, enabling the targeted conjugation of proteins to other thiol-containing molecules or surfaces. The inclusion of a PEG12 spacer enhances the solubility and flexibility of the compound, reducing the possibility of steric hindrance during the conjugation process and increasing the stability of the conjugate in biological environments. The PEGylation aspect also helps to increase the bioavailability and decrease the immunogenicity of the conjugated molecules.