Nanometer scale rafts built from DNA tiles

Hierarchical self-assembly was used to construct meso-scale DNA objects as eventual templates for molecular electronic circuitry. DNA tiles were assembled from single-stranded precursors. The tiles measure 4 nm×12 nm×2 nm. They can be programmed to self-assemble into larger objects, such as a 4-tile raft 37 nm long. The composition and structure of the DNA rafts were characterized in solution by biochemical assays. Rafts were imaged on mica substrates under isopropanol by non-contact mode AFM, or alternately, were deposited on silicon wafers and imaged by non-contact mode AFM in air.