(2-pyridyldithio)-PEG4-alcohol

(2-pyridyldithio)-PEG2-alcohol is a PEG linker which contains a pyridyl disulfide moiety and an alcohol group. The pyridyl disulfide group can react with thiol groups of proteins over a wide range of pH level. The hydroxyl group allows for further derivatization of the compound. The hydrophilic PEG linker increases the water solubility of the compound.