Journal of Vacuum Science & Technology A, Vol.12, No.4, 1895-1903, 1994
DNA Nanoconstructions
The control of structure on the nanometer scale is central to nanotechnology. We are pursuing this end with synthetic DNA, whose sequence is selected by sequence symmetry minimization algorithms, so that it can form branched junctions. These structures can be ligated together in the same way that linear DNA is ligated in molecular cloning. Ligating branched structures generates stick figures whose edges consist of double helical DNA and whose vertices are branch points. We have built a DNA molecule whose helix axes have the connectivity of a cube. The vertices are separated by two helical turns of DNA; hence the plectonemic nature of DNA makes this molecule a hexacatenane, each of whose cyclic strands corresponds to a face. We have developed a solid-support-based procedure to implement these constructions. Using the solid-support-based methodology we have constructed a molecule whose helix axes have the connectivity of a truncated octahedron. This figure contains 14 faces, of which six are ideally square and eight are hexagonal; this Archimedean polyhedron contains 24 vertices and 36 edges. Control of topology is strong in this system, but control of three-dimensional (3D) structure remains elusive. Our key aim is the formation of prespecified two-dimensional and 3D periodic structures. Applications envisioned include nanomanipulators and scaffolding for molecular electronic devices.
Keywords:NUCLEIC-ACID JUNCTIONS;SCANNING TUNNELING MICROSCOPE;SINGLE-STRANDED-DNA;BRANCHED JUNCTIONS;DESIGN;CONSTRUCTION;SCALE;RNA;MANIPULATION;FLEXIBILITY