AFM Measurements of DNA Molecule Electron Transport Properties

Deoxyribonucleic acid (DNA) has been considered as a possibility for molecular electronics. Because DNA is able to recognize other molecules—other strands of DNA—and because it binds together with similar DNA strands in a very unique way, scientists have suggested the possibility of using DNA as an electronic circuit without having to build in any other circuitry. The DNA would bind with other similar DNA strands that it recognizes and then use the connecting properties of the DNA to create a self-assembled biological wire for electrical conduction. Until recently, uncertainty existed about whether DNA could conduct at all, and if it could, how well it could conduct. Scientific speculations ranged from DNA being a superconductor to a complete insulator. Recent research, however, by Dr. Sidney R. Cohen in collaboration with Dr. Ron Naaman and Dr. Claude Nogues of the Weizmann Institute of Science, Scanned Probe Microscopy Unit, in Rehovot, Israel, aided by the enabling technologies of ultra-high-resolution microscopy and negative-stiffness vibration isolation, has shed new light on the electrical transport properties of DNA, focusing on the capacity of single molecules of DNA to transport current along individual strands.