Cationic Amphiphilic Star and Linear Block Copolymers: Synthesis, Self-Assembly, and in Vitro Gene Transfection
journal contributionposted on 12.09.2011, 00:00 by Anu M. Alhoranta, Julia K. Lehtinen, Arto O. Urtti, Sarah J. Butcher, Vladimir O. Aseyev, Heikki J. Tenhu
A series of amphiphilic star and linear block copolymers were synthesized using ATRP. The core consisted of either polystyrene (PS) or poly(n-butyl acrylate) (PBuA), having different glass-transition (Tg) values. These polymers were used as macroinitiators in the polymerization of the cationic 2-(dimethylamino)ethyl methacrylate (DMAEMA). The polymers were used to study the effects of polymer architecture and flexibility on the self-assembling properties, DNA complexation, and transfection. All polymers formed core–shell micelles in aqueous solutions and condensed plasmid DNA. Linear PDMAEMA-PBuA-PDMAEMA has transfection efficiency comparable to PEI25K in ARPE19 cell line. Glassy state of the micellar core and star-shaped architecture decreased the DNA transfection compared with the rubbery and linear polymer structures. The polymers showed low cellular toxicity at low nitrogen/phosphate (n/p) ratios.