PLGA cationic nanoparticles, obtained from nano-emulsion templating, as potential DNA vaccines

Polymeric nanoparticles offer advantageous characteristics as gene-delivery vectors such as biocompatibility and biodegradability. With this aim, a smart and innovative strategy was followed here: Cationic PLGA nano-emulsions, prepared by a low energy method, were used as templates to obtain cationic nanoparticles (NPs) able to easily complex with nucleic acids (i.e. plasmid DNA) by electrostatic interactions. The strategy employed to produce stable positively-charged nanoparticles was the use of non-ionic/cationic surfactant mixtures to stabilize template nano-emulsions. This methodology allowed obtaining nanoparticles with reproducible nanometric sizes and positive zeta potential values, appropriate to successfully complex with nucleic acids, resulting in nanometric spherical polyplexes. Nanoparticles, plasmids and polyplexes proved to be biocompatible at the optimal concentration. Therefore, we can conclude that we have designed a novel strategy to efficiently obtain cationic polymeric nanoparticles that can be a promising approach to act as novel non-viral gene-delivery vectors, useful for many applications in gene therapy, such as gene vaccines.