Single molecule study of DNA conductivity in aqueous environment.
The dc electrical conductivity of double stranded DNA is investigated experimentally. Single DNA molecules are manipulated with subpiconewton force and deposited on gold nanoelectrodes by optical traps. The DNA is modified at its ends for specific bead attachments and along the chain to favor charge transfer between the DNA base pair stack and the electrodes. For an electrode separation of 70 nm we find, in aqueous environment, electrical resistances above 100 G Omega indicating that even for weak stretching the double helix is almost insulating at this length scale.
Legrand
O
O
Laboratoire Pierre Aigrain, Département de Physique de l'Ecole Normale Supérieure, 24 rue Lhomond, 75005 Paris, France.
Côte
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D
Bockelmann
U
U
D003198:Computer Simulation; D004247:DNA / Q000737:chemistry*; D004548:Elasticity; D004553:Electric Conductivity; D004563:Electrochemistry / Q000379:methods*; D008956:Models, Chemical; D013314:Stress, Mechanical; D014867:Water / Q000737:chemistry*
D014867:Water; D004247:DNA