Poly(ethylene glycol)-block-polyethyleneimine

Gene therapy using polymeric nonviral vectors promises considerable advances in the treatment of many genetic and acquired diseases due to the carrier safety and low immunogenicity profiles. 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.