(482c) Aunps-Polyplex-Electroporation Enhanced DNA and RNA Delivery

Non-viral methods have been explored as replacements of viral systems for DNA or RNA delivery to mammalian cells for their low toxicity and immunogenicity. In nonviral systems, chemical methods, including lipoplex and polyplex, exhibit advantages on probe carry, protection, and condenation while physical methods, such as biolistics and electroporation, facilitate fast, directial, and efficient probe delivery. Great improvements have been achieved on each approach over the years. However, they have yet to reach levels competitive to their viral counterparts on the delivery efficiency, cell viability, and targeting specificity. We hypothesize that the combination of some physical and chemical methods could improve the performance of nonviral delivery systems. Specifically, we immobilized polyplex (a chemical approach) on gold nanoparticles/nanorods and delivery them into cells through electroporation (a physical approach). Conjugating with AuNPs helps minimize the cytotoxicity  concerns from polyplex after cytoplasmic release while still retain good probe protection in serum. Combining with electroporation, conjugated polyplex (AuNPs-Polyplex) showed quick delivery and significant enhancement on the transfection efficiency whil no obvious increase of toxicity. Specifically, gold nanoparticles (AuNPs) of various sizes and geometries were conjugated with polyplex of polyethylenimine (PEI)-plasmid and PEI-siRNA. The conjugated nanoparticles were then mixed with cells and electroporated using a commercial instrument and a serpentine flow-through electroporation (SFE) microsystem. These nanoparticles help enhance gene delivery to mammalian cells with better cellular uptake of molecular probes and reduced adverse effects associated with nonviral delivery approaches. Such a combination of physical and chemical delivery concept may stimulate further exploration in the delivery of various therapeutic materials for both in vitro and in vivo applications.