Self-assembly, manipulation, and discrimination of DNA molecules by scanning tunneling microscope (STM) on solid surfaces

DNA base molecules form novel low-dimensional superstructures on Cu(111) surfaces through hydrogen bonding among molecules and through their epitaxial growth on the surface. The chemical inertness of the Cu(111) substrate allows the molecules to diffuse over the surface to self-assemble spontaneously into their own unique structures. Molecular orbital calculations explain the mechanism of the observed self-assemblies induced by base-base hydrogen bonding. High-resolution molecular imaging and manipulation of DNA base molecules and DNA oligomers have also been successfully carried out on SrTiO3(100) and Cu(111) surfaces under ultra-high vacuum conditions by STM.