Interaction of reducible polypeptide gene delivery vectors with supported lipid bilayers: pore formation and structure-function relationships

Real-time atomic force microscopy (AFM) in aqueous buffer has been used to probe interactions of synthetic disulfide-linked polypeptide gene delivery vectors with supported phospholipid bilayers. Disruption of the membranes was apparent in AFM, and the extent of surface heterogeneity and hole (pore) formation was evaluated by depth and area-profiling image analysis. The overall extent of membrane disruption varied with the reducible polycation peptide sequence and block structure and was found to be correlated with the overall degree of transgene expression in two representative cell lines.