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Peroxide Doping of DNA Enables Dissipative Impedance
204th Meeting of Electrochemical Society, Abstract 1379, Orlando 2003
Merrill Garnett and C.V. Krishnan
Garnett McKeen Lab, Inc.
We have reported a method of non-steady state impedance showing catalytic discharge of capacitance by a palladium-lipoic acid polymer (1,2). The capacitance plot reverses and extends into the upper left quadrant of the complex plane. The method involves micro-polarization of the mercury electrode in narrow voltage bands (2.0 mv) appearing at slightly positive voltages. This allows minute amounts of mercurous ions to dope liquid crystal polymers. Now we attempt to show this process in DNA (Sigma-ct) to explore DNA semi-conduction. Such behavior would introduce waveguide efficiency to charge transfer within DNA and between DNA and its milieu. Difficulty locating dissipative bands within DNA was overcome by doping the system with H2O2 and by coating (3,4) with the dielectric hyaluronic acid (HA). Thus the system became ambipolar (5), having both p and n type dopants.
Electro-analysis in the complex plane display was performed in a purged solution (0.055 M sodium acetate, 0.9 mg/ml each of DNA and HA. 0.27% H2O2) at pH4.89 with an Ecochemie Autolab using log series of frequencies from 1 kHz. to 50mHz. The Bode plot reaches negative resistivity (fig 1) and the complex plane display (fig 2) shows discharge into the upper left quadrant. This kind of impedance was forecast in theory by Cao (6). The prepared sample was dried on a glass slide for phase microscopy (900x) (fig 3). The sample is seen to have transient radiative fern packing. The use of dopants, oxyradicals, and a prepared environment to facilitate charge transfer in DNA, recalls that such reactions occur within the dynamics of the living state. Such activity within the hydration grooves does not minimize the path through the gene base pi-bonds (7). The presence of the two paths however modest, allows mutual inductance. That interaction produces energy reflections, oscillation, and propagation, and a model with the efficiency of multi-stranded transmission cable.
The variety of theories and data in the literature of DNA charge transfer should not be considered contradictory. Rather they contribute to the emergence of an intricate equivalent electronic circuitry.
References:
1. Krishnan, C.V., Garnett, M., 1st Spring Meeting of the Int' 1 Soc. Of Electrochem.,Alicante,  Spain, 2003, Abstract P06
2. Krishnan, C.V., Garnett, M., Remo, J.L., 203rd Meeting of ECS, Paris, 2003, Abstract 2703
3. Garnett, M., Remo,. J.L, 198th Meeting of ECS, Phoenix.,2000, Abstract 1152
4. Garnett, M., Krishnan, C.V, 201st Meeting of ECS, Phil., 2002 Abstract 78
5. Emiliani, V., Frova, A., Prisilla, C., Superlattices and Micro-structures, 20, No.1,1-5, 1996
6. Cao, C., Electrochim.Acia,35,No5,837-44,1990
7. Wan, C., Fiebig,T.,Schicmann,), Barton,JK,Zewail, A.H., Proc.Nat.Acad.Sci,USA,97, 14052,2000, and references therein.



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