Analytical Sciences

Abstract − Analytical Sciences, 19(1), 23 (2003).

M-DNA: a Self-Assembling Molecular Wire for Nanoelectronics and Biosensing
Shawn D. WETTIG,* Chen-Zhong LI,*,** Yi-Tao LONG,*,** Heinz-Bernhard KRAATZ,**  and Jeremy S. LEE* 
*Department of Biochemistry, University of Saskatchewan, 107, Wiggins Road, Saskatoon, SK, S7N 5E5 Canada
**Department of Chemistry, University of Saskatchewan, 110, Science Place, Saskatoon, SK, S7N 5C9 Canada
M-DNA is a complex between divalent metal ions such as Zn2+ and duplex DNA which forms at pH 8.5. Unlike B-DNA, M-DNA does not bind ethidium so that M-DNA formation can be monitored conveniently by an ethidium fluorescence assay. M-DNA was shown to be a better conductor than B-DNA by fluorometric measurements of electron transport in donor-acceptor labelled duplexes; by direct conductivity measurements of M-DNA bound between gold electrodes and by cyclic voltammetric studies on ferrocene labelled duplexes attached to gold microelectrodes. As is the case with B-DNA, M-DNA can self-assemble into a variety of structures and is anticipated to find widespread use in nanoelectronics and biosensing.