title: Electrochemical evaluation of alternating duplex-triplex conversion effect on the anthraquinone-photoinjected hole transport through DNA duplex immobilized on a gold electrode.
abstract: Amperometry was employed to characterize the anthraquinone (AQ)-photoinjected hole transport through a 20-mer oligodeoxynucleotide (ODN) duplex, as immobilized on the surface of a gold electrode, and its triplex forms converted by association with several third oligopyrimidine (OPD) short strands. While the cathodic photocurrent was observed upon irradiation at 365 nm of the AQ photosensitizer linked to the end of DNA duplex, a marked lowering of the current density was identified to occur by the triplex formation of a duplex with a given third OPD short strand. The photocurrent through the DNA duplex showed a reversible fall-rise response concomitant with alternating association-dissociation cycle of the OPD short-strand, as regulated by temperature change around the corresponding melting temperature of the DNA triplex. Both the switched photoirradiation and the thermally alternating duplex-triplex conversion could provide tools of regulating the DNA hole transport.
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Katsura Campus, Kyoto 615-8510, Japan. tanabeka@scl.kyoto-u.ac.jp
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Tanabe
authors.forename: Haruka
authors.initials: H
authors.lastname: Iida
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Haruna
authors.forename: Taku
authors.initials: T
authors.lastname: Kamei
authors.forename: Akimitsu
authors.initials: A
authors.lastname: Okamoto
authors.forename: Sei-ichi
authors.initials: S
authors.lastname: Nishimoto
mesh_terms: D000880:Anthraquinones / Q000737:chemistry*; D001483:Base Sequence; D002412:Cations; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D006046:Gold / Q000737:chemistry*; D009693:Nucleic Acid Hybridization; D009841:Oligonucleotides / Q000737:chemistry; D010777:Photochemistry; D017319:Photosensitizing Agents / Q000737:chemistry
chemical_list: D000880:Anthraquinones; D002412:Cations; D009841:Oligonucleotides; D017319:Photosensitizing Agents; C051802:triplex DNA; D006046:Gold; D004247:DNA