Mal-amido-PEG3-acid contains a maleimide group and a terminal carboxylic acid. The PEG spacer increases the aqueous solubility of the resulting compound. The terminal carboxylic acid readily reacts with primary and secondary amine under EDC, DCC, HATU or other amide coupling conditions to form a stable amide bond. The maleimide group reacts specifically with a thiol group to form a covalent C-S bond, enabling the bioconjugation with a thiol bearing molecules.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.