Maleimide PEG NHS is a heterobifunctional PEG derivative that can react with both thiol and amine groups. NHS esters react with deprotonated primary amines, therefore, the reaction requires neutral to basic pH values to proceed. The maleimide group reacts with available –SH groups from naturally occurring or mutagenically derived cysteine residues. Maleimide groups react with sulfhydryl groups at pH 6.5~7.5 at room temperature to form stable thioether bonds.

Maleimide PEG NHS is a heterobifunctional PEG derivative that can react with both thiol and amine groups. NHS esters react with deprotonated primary amines, therefore, the reaction requires neutral to basic pH values to proceed. The maleimide group reacts with available –SH groups from naturally occurring or mutagenically derived cysteine residues. Maleimide groups react with sulfhydryl groups at pH 6.5~7.5 at room temperature to form stable thioether bonds.