Peroxide
Doping of DNA Enables Dissipative Impedance
204th
Meeting of Electrochemical Society, Abstract 1379, Orlando 2003
Merrill Garnett and C.V. Krishnan
Garrett
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.,
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.