The structure of DNA by direct imaging and related topics

Super-hydrophobicity is a well-known and studied phenomenon in the field of surface sciences. In this review we report a novel approach that exploits micro-fabricated super-hydrophobic surfaces for the oriented and self-organized deposition and suspension of DNA filaments and other macromolecules of biological interest. The self-assembled structures obtained with this approach can be used for the characterization of the biological compounds with several methods such as electron microscopy, X-ray diffraction, Raman and SERS spectroscopies. Besides imaging, the described method has been applied in several fields such as the sensing of few molecules in diluted solutions and innovative templating growth. We will focus in particular on the direct imaging of DNA molecules by Transmission Electron Microscopy with the capability to resolve structural details of the double helix down to a resolution of 1.5 angstrom. The review starts with a brief historical note on the discovery of the DNA structure and continues with the results obtained by our group along the last 10 years of activity.