title: Comparing Charge Transport in Oligonucleotides: RNA:DNA Hybrids and DNA Duplexes.
abstract: Understanding the electronic properties of oligonucleotide systems is important for applications in nanotechnology, biology, and sensing systems. Here the charge-transport properties of guanine-rich RNA:DNA hybrids are compared to double-stranded DNA (dsDNA) duplexes with identical sequences. The conductance of the RNA:DNA hybrids is ∼10 times higher than the equivalent dsDNA, and conformational differences are determined to be the primary reason for this difference. The conductance of the RNA:DNA hybrids is also found to decrease more rapidly than dsDNA when the length is increased. Ab initio electronic structure and Green's function-based density of states calculations demonstrate that these differences arise because the energy levels are more spatially distributed in the RNA:DNA hybrid but that the number of accessible hopping sites is smaller. These combination results indicate that a simple hopping model that treats each individual guanine as a hopping site is insufficient to explain both a higher conductance and β value for RNA:DNA hybrids, and larger delocalization lengths must be considered.
authors.affiliation: Electrical and Computer Engineering Department, University of California Davis , Davis, California 95616, United States.
authors.forename: Yuanhui
authors.initials: Y
authors.lastname: Li
authors.affiliation: Electrical and Computer Engineering Department, University of California Davis , Davis, California 95616, United States.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Artés
authors.affiliation: Department of Electrical Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Jianqing
authors.initials: J
authors.lastname: Qi
authors.affiliation: Department of Plant Pathology, University of California Davis , Davis, California 95616, United States.
authors.forename: Ian A
authors.initials: IA
authors.lastname: Morelan
authors.affiliation: Department of Plant Pathology, University of California Davis , Davis, California 95616, United States.
authors.forename: Paul
authors.initials: P
authors.lastname: Feldstein
authors.affiliation: Department of Electrical Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: M P
authors.initials: MP
authors.lastname: Anantram
authors.affiliation: Electrical and Computer Engineering Department, University of California Davis , Davis, California 95616, United States.
authors.forename: Joshua
authors.initials: J
authors.lastname: Hihath
mesh_terms: D004247:DNA / Q000737:chemistry*; D004579:Electron Transport; D009841:Oligonucleotides / Q000737:chemistry*; D011789:Quantum Theory; D012313:RNA / Q000737:chemistry*
chemical_list: D009841:Oligonucleotides; D012313:RNA; D004247:DNA