Poly(aminoether)-gold nanorod assemblies for shRNA plasmid-induced gene silencing

Gold nanorods (GNRs) have emerged as promising nanomaterials for biosensing, imaging, photothermal hyperthermia treatments, and therapeutic delivery for several diseases. We generated poly(aminoether)-GNR nanoassemblies using a layer-by-layer deposition approach based on the 1,4C-1,4Bis polymer from a library recently synthesized in our laboratory. Subtoxic concentrations of 1,4C-1,4Bis-GNR nanoassemblies were employed to deliver expression vectors that express shRNA ("shRNA plasmid") against firefly luciferase gene to knock down expression of the protein constitutively expressed in prostate cancer cells. The role of hydrodynamic size and zeta potential in determining nanoassembly mediated luciferase silencing was investigated. Finally, the theranostic potential of 1,4C-1,4Bis-GNR nanoassemblies was demonstrated using live cell two-photon induced luminescence bioimaging. Our results indicate that poly(aminoether)-GNR nanoassemblies are a promising theranostic platform for delivery of therapeutic payloads capable of simultaneous gene silencing and bioimaging.