Interaction between polyether- poly (2-dimethylaminoethyl methacrylate) copolymers and phospholipid model vesicles – implications for gene delivery efficiency

Our previous studies have demonstrated that surfaceactive copolymers of Pluronic® surfactants and tertiary amino polycations such as poly (2-dimethylaminoethyl methacrylate) (PDMA) possess an enhanced DNA transfection efficiency compared to PDMA homopolymers. In order to understand the mechanism of such action, we conducted model studies of the interaction of polymer with phospholipid vesicles and cell membranes. Three cationic methacrylate polymer systems were used in this study: PDMA homopolymer, and PEO-b-PDMA and Pluronic L92-b-PDMA block copolymers. The results showed that PDMA and PEO-b-PDMA only interact with the surface of the vesicles, whereas L92-b-PDMA interacts strongly with the inner hydrophobic segment of the vesicles. The studies show that the strong interaction between L92-b-PDMA and phospholipid membrane could be used to explain the enhanced transfection efficiency previously shown by the Pluronic L92-b-PDMA copolymer.