4-Arm PEG-amine (MW 5000)

4-Arm PEG-amine (MW 5000) is a PEG Linker. The reactive primary amine or NH2 rapidly react with aldehyde, ketone to form imine. Imine upon further reduction forms secondary amine via reductive amination. Amine reacts with activated carboxyl acid, NHS ester to form stable amide bonds. 4-Arm PEG reagents are useful crosslinking reagent and used for dr_ug delivery.