Synthesis and Characterization of a Nano-Polyplex system of GNRs-PDMAEA-pDNA: An Inert Self-Catalyzed Degradable Carrier for Facile Gene Delivery.

Engineering molecules at nano-scale is a promising approach in targeting and curing diseases. In this research, fabricated new hybrid system called nano-polyplex represents an example of the molecular engineering at nano-scale. Polymer of PDMAEAs with four different molecular weights were synthesized using the RAFT method, attached onto the gold nano-rod surface, which modified and produced a safe novel system with an average size less than 100 nm. The hybrid system was characterized by ultra violet-visible spectrophotometer (UV-Vis), dynamic light scattering (DLS), 1H NMR, gel permeation chromatography (GPC), Fourier transform-infrared (FT-IR) spectroscopy, Zeta potential analyzer and transmission electron microscopy (TEM). Features of higher transfection and lower toxicity compared to the previously reported polyplex of PDMAEA, as well as the gold standard PEI, have been shown in all molecular weights and defined N/P ratios (10-200). The ideal physicochemical properties for escaping from the cell barriers, covering the large volume of genetic material (pDNA) and high efficiency of loading polyplexes on GNRs' surface make it an ideal carrier. The results of this effort pave way in designing a new generation of nanoparticle-based delivery systems for nucleic acid therapy and gene editing.