Synthesis of polyethylenimine grafted with copolymers of polyethylene glycol and polycaprolactone and its potential for siRNA delivery

Copolymers mPEG-PCL were prepared and grafted onto polyethylenimine (PEI) to synthesize copolymers mPEG-PCL-g-PEI with low cytotoxicity. The mPEG-PCL-g-PEI could condense siRNA to form nanoparticles with positive zeta potential. These nanoparticles could delivery siRNA into cells to effectively inhibit the expression of target gene, which suggested that mPEG-PCL-g-PEI could serve as a highly efficient vector for siRNA delivery.