title: In situ electrochemical distance tunneling spectroscopy of ds-DNA molecules.
abstract: The electrical conductance of ds-DNA duplexes containing 8-14 base pairs modified at both ends with a -(CH(2))(6)-SH linker was measured in a buffered aqueous solution using electrochemically controlled distance tunneling spectroscopy. The tunneling experiment with self-complementary 5'-(GC)(n)()-3'-(CH(2))(6)-SH (n = 4-7) duplexes attached covalently to a gold STM tip and a Au(111) electrode shows a wide distribution of currents independent of the ds-DNA length. The voltage-induced horizontal orientation of ds-DNA within the junction results in decreased electrical conductance. The lower currents are also observed for ds-DNA molecules containing a single CA base mismatch.
authors.affiliation: Department of Chemistry and Biochemistry, California State University, Long Beach, 1250 Bellflower Boulevard, Long Beach, California 90840, USA.
authors.forename: Emil
authors.initials: E
authors.lastname: Wierzbinski
authors.forename: Justin
authors.initials: J
authors.lastname: Arndt
authors.forename: William
authors.initials: W
authors.lastname: Hammond
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Slowinski
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods*; D013057:Spectrum Analysis / Q000379:methods*
chemical_list: D004247:DNA