DNA electronics

DNA forms a self-assembled structure that we can control by programming the base sequence, thus has the potential as a bottom-up material for nano-templates and nano-machines, and for use as a nano-electronics material in one-dimensional molecular wires. In this review article, we focus on electric conduction, doping and the electronic states of DNA and investigate the potential use of DNA as a nano-electronics material. Various reports have appeared describing the conduction property of DNA. Some of these have described the transport property of DNA as an insulator, while others claimed that it resembled a semiconductor or metal. However, detailed analysis of the base sequences and experimental environments have revealed the importance of the water attached to the DNA. Systematic considerations of electric conduction, doping and electronic states show that DNA is an insulator, and that periodic DNA can be a wide-gap semiconductor. Doped DNA in a vacuum could be used as a nano-scale electron transport material, and DNA in the atmosphere could be used as a nano-scale ion transport material. (c) 2006 Elsevier B.V. All rights reserved.