4-Arm PEG-NH2 (MW 20000)

4-Arm PEG-NH2 (MW 20000) (4-Arm PEG-amine (MW 20000)) is a multi-arm PEG derivative with amine groups at each end of four arms attached to a pentaerythritol core. The reactive primary amine or NH2 groups can react rapidly with activated carboxylic acids such as NHS esters to form stable amide bonds.