Interactions of a hydrophobically modified polycation with zwitterionic lipid membranes.

The interactions between synthetic polycations and phospholipid bilayers play an important role in some biophysical applications such as gene delivery or antibacterial usage. Despite extensive investigation into the nature of these interactions, their physical and molecular bases remain poorly understood. In this Article, we present the results of our studies on the impact of a hydrophobically modified strong polycation on the properties of a zwitterionic bilayer used as a model of the mammalian cellular membrane. The study was carried out using a set of complementary experimental methods and molecular dynamic (MD) simulations. A new polycation, poly(allyl-N,N-dimethyl-N-hexylammonium chloride) (polymer 3), was synthesized, and its interactions with liposomes composed of 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC) were examined using dynamic light scattering (DLS), zeta potential measurements, and cryo-transmission electron microscopy (cryo-TEM). Our results have shown that polymer 3 can effic...