Impedance measurements on a DNA junction.
1 microm double-stranded DNA molecules are immobilized between pairs of gold and pairs of platinum microelectrodes with gaps of 0.4 and 1 microm, respectively, and their electrical characteristics are determined under the application of constant and sinusoidal bias voltages. Due to their extremely high impedance for constant voltage bias, the samples of DNA are excellent insulators; however, their impedances show strong frequency dependence in the range of 10 Hz-7.5 MHz. Favorable response in the gold electrodes is attributed to the higher ability of DNA molecules to bridge the narrower gold electrode gaps in contrast to that in the wider platinum junctions.
Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, USA.
Sungmin
S
Hong
Luis A
LA
Jauregui
Norma L
NL
Rangel
Huan
H
Cao
B Scott
BS
Day
Michael L
ML
Norton
Alexander S
AS
Sinitskii
Jorge M
JM
Seminario
D004247:DNA / Q000737:chemistry*; D017097:Electric Impedance; D004566:Electrodes; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry
D010984:Platinum; D006046:Gold; D004247:DNA