Amphiphilic Block Copolymer Micelles for Gene Delivery

Gene therapy is a promising method to treat acquired and inherited diseases by introducing exogenous genes into specific recipient cells. Polymeric micelles with different nanoscopic morphologies and properties hold great promise for gene delivery system. Conventional cationic polymers, poly(ethyleneimine)(PEI), poly(L-lysine)(PLL), poly(2-dimethyla-minoethyl methacrylate)(PDMAEMA) and novel cationic polymers poly(2-oxazoline)s(POxs), have been incorporated into block copolymers and decorated with targeting moieties to enhance transfection efficiency. In order to minimize cytotoxicity, nonionic block copolymer micelles are utilized to load gene through hydrophilic and hydrophobic interactions or covalent conjugations, recently. From our perspective, properties(shape, size, and mechanical stiffness, etc.) of block copolymer micelles may significantly affect cytotoxicity, transfection efficiency, circulation time, and load capacity of gene vectors in vivo and in vitro. This review briefly sums up recent efforts in cationic and nonionic amphiphilic polymeric micelles for gene delivery.