O-Carboxymethyl-chitosan/organosilica hybrid nanoparticles as non-viral vectors for gene delivery

Polymeric non-viral vectors, such as chitosan nanoparticles show good biocompatibility, but low transfection efficiency. The objective of this study was to improve the transfection efficiency of chitosan based non-viral vectors by using o-carboxymethyl-chitosan which is a kind of water-soluble chitosan derivative and also has good biocompatibility. O-Carboxymethyl-chitosan-organosilica hybrid nanoparticles (CMG NPs) were synthesized through a rapid one-step aqueous synthetic approach for gene delivery. The size of nanoparticles was 276 ± 25 nm and zeta potential was 31.6 ± 0.4 mV in deionized water. Zeta potential increased with the decrease of pH, and it had been discovered that pH = 5.5 is the best point for CMG NPs to bond with plasmid DNA. DNA inclusion and integrity was evaluated by gel electrophoresis, and it is indicated that CMG NPs could protect DNA against DNase I and serum degradation. The results of MTT for cell viability and in vitro transfection also support the idea that CMG NPs could be used as efficient and safe vectors for gene delivery.