The development of ever smaller electronic circuits may greatly benefit from the use of bottom-up strategies for generating more efficient and versatile fabrication methods of nanosized elements than by the traditional top-down approach. One of the most promising approaches is based on the self-recognition of DNA, which allows the construction of arbitrarily shaped nanoobjects with high reproducibility. The nanostructures need to be functionalized with electrically conducting material, turning them into good wires or otherwise conducting circuit elements.

Here we demonstrate the formation of Au nanostructures based on DNA Origami structures, which are first formed by self-assembly and metalized in a subsequent step. Following one strategy, DNA nanomolds are employed, inside which gold deposition by site-specific attached seeds starts the metalization. These structures can be subsequently enhanced by internal gold deposition. During this step, the walls of the nanomolds serve as constraints. We were able to prove the metallic nature of these nanostructures by performing temperature-dependent charge transport measurements along the nanostructures. These gold nanostructures can be used for contacting DNA assemblies, as well. Transport through these assemblies is strongly nonlinear and shows a decrease in conductance towards low temperatures.

Using a different approach, the shape of the nanowires can be controlled. We use DNA-origami templates which are functionalized on their surface in order to create desired shapes of the metallic nanostructures. Metallic nanoparticles are attached to the functional sites and enhanced through electroless deposition to form continuous conductive structures. Temperature-dependent charge transport measurements show that the dominating charge transport mechanisms along these wires is dominated by hopping effects. Both methods show that the DNA Origami technique serves as a platform for the creation conducting nanowires with well-defined shape.