Smart PEGylated gold nanoparticles for the cytoplasmic delivery of siRNA to induce enhanced gene silencing

A novel cytoplasmic delivery system of siRNA was developed by complexation between poly(ethylene glycol)-blockpoly(2-(N,N-dimethylamino)ethyl methacrylate) copolymer (PEG-PAMA) and gold nanoparticles (GNPs), followed by the immobilization of siRNA bearing a thiol group (SH-siRNA). The PEGylated GNPs containing SH-siRNA showed a significant RNAi activity in HuH-7 cells.