Linear polyethylenimine-block-poly(ethylene glycol)

Due to their low immunogenicity profiles, polymeric nonviral vectors have shown promise in advancing the treatment of many severe genetic and acquired diseases via gene therapy. Poly(ethyleneimine) is one of the most commonly used cationic polymers for gene delivery applications. Copolymers of PEI and hydrophilic poly(ethylene glycol) have been designed to provide a stealth-like shield around polymer/DNA complexes, reducing nonspecific interactions, inhibiting activation of the reticuloendothelial system, and prolonging the half-life of the complexes in the blood.