| |
| |
|
Poly-MVA(LAPd) Published Research
Page 2 of 3 pages
| |
| |
|
Article - N
|
"Dissipative Impedance
in a Doped Liquid Crystal"
(Krishnan and Garnett, 1st Spring Meeting
of the International Society of Electrochemistry, Abstract P06, Spain 2003)
C. V. Krishnan, M. Garnett
Garnett McKeen Lab, Inc.
150 Islip Ave. Suite 6,, NY 11751 USA
Liquid crystal materials form macro-molecular arrays which are altered by
electric or magnetic fields (Freedericks transition)[1] This electronic reactivity makes them interesting substances
for electrochemical study. The liquid crystal palladium-lipoic acid polymer complex (PLA)[2,3], an investigative
chemotherapy agent, exhibits a novel distortional impedance. This plot is restricted to a narrow (10mv.) voltage
range near the zero volts polarization threshold of the mercury electrode [figs1-3: Z plot, Bode, CV]. The initial
capacitive arc rises to form a counter-clockwise curve which moves through zero DC impedance through the upper
left quadrant of the complex plane. This is an example of an Hg+1 dopan effect on the liquid crystal. The negative
DC resistances are interpreted as charge dissipation. The dissipation is consistent with charge transfer. PLA reduces
DNA [2, 3] . The mechanism for the charge transfer is believed to derive from the liquid crystal structure. In
solid state crystals there is a finite array of uniform unit cells with a common dimension [4, 5]. The array propagates
a fundamental frequency by lattice reflections and conduction band state. The liquid crystal mimics the solid crystal.
We attempt to define the differences by looking at the influences of solution conditions including pH and temperature,
and also by response to magnetic fields. Liquid crystals are a novel way to catalyze charge transfer in biochemical
systems.
References
1. Collings, PJ. Liquid Crystals, Princeton Univ. Press, 1990
2. M.Garnett, U.S. Patent No 5, 436,093, 1995
3. M. Garnett, and J.L. Remo, Microfabricated Systems and Mems V.
Proc. ECS.2000-19:185-190, 2000.
4. D.C. Wallace, Thermodynamics of Crystals, Dover Pub., 1997
5. Kittel, C., Introduction to Solid State Physics-6th ed., John Wiley, 1986.
|
Article - M
|
"Dopant Catalyzed Charge
Dissipation in a Liquid Crystal"
(Krishnan and Garnett, 203rd Meeting of Electrochemical
Society, Abstract 2703, Paris 2003)
C.V.Krishman, Merrill Garnett And John L. Remo
Garnett McKeen Lab Inc.
150 Islip Ave. Suite 6
Islip, New York 11751, USA
Palladium and lipoid acid have been combinated in 1:1 stoichiometry
to form a liquid crystal polymer complex (PLA). PLA is an investigative chemotherapy compound which transfers charge
to DNA (1,2). PLA dries to form a fern pattern (fig.1), and undergoes a geometric transform from magnetic fields
introduced during drying (Freedericks transition )(fig.2). PLA was synthesized in its 1:1 core form for this study,
without edition of co-reactants used in its clinical formulation. The PLA is studied by modification of electronic
impedance spectroscopy in which controlled charge dissipation is allowed at the threshold of electrode polarization.
This attempts to simulate the ion streaming in cell membranes which accompanies biologic oscillatory depolarization
and repolarization, best studied in cardiac and nerve tissue.
Alkaline PLA (pH range from 7.3 to 12.3) at .04m, calculated monomer, is diluted with de-ionizedter. The PLA contains
NaCI from the method of synthesis, and no additional background electrolyte is necessary. The diluted PLA is analyzed
in an Ecochemie Autolab electro-chemistry system using a PAR mercury electrode stand. Impedance spectroscopy is
performed at mercury oxidation threshold voltages to locate this boundary condition. A log series of 49 frequencies
from1KHz to 50MHz is scanned with 5 mv perturbations. Within 10 mv. bands, in a range from+.01 to +.38 V as a function
of pH, EIS produces a conventional capacitive segment followed by a large counter-clockwise (reverse) curvature
extending into the upper left quadrant of the complex plane(+.01 V: fig 3). The counter-clockwise curve has a smooth
circle fit. An equivalent circui- RI(Q1<R2_WI>) is expressed. A convergence to negative DC resistance, appears
to be a discharge of a capacitive layer. The narrow voltage band is thought to limit the electrode corrosion to
a small amount of Hg+1, which acts as a dopant hole in the PLA liquid crystal.
The magnitude of the charge dissipation (current reversal), is correlated with the movement of both electrons and
cation hole, a condition which has been called ambipolar and modeled in depth(3).
This catalytic charge transfer in a liquid
crystal is a new paradigm in cancer chemotherapy.
References:
1. Garnett,M., U.S.Patent No 5463,093-Oct.31,1995
2. Garnett, M., Remo J.L.,
Microfabricated Systems and Mems V, Proc., 2000-19:185-190,ECS,2000.
3. Emiliani,V ., Frova A., Presilla,C,
Superlattices and Microstructures,20: No.1,1-5,1996
|
Article - l
|
"Duplex semiconductor
behavior of mercury
electrode in aqueous solutions"
(Krishnan and Garnett, 226th American Chemical Society National Meeting, Abstract Inor.0028, New York 2003)
C.V. Krishnan, and Merrill Garnett
Garnett McKeen Lab, Inc.
150 Islip Ave. suite 6, Islip, NY 11751 USA
Impedance and admittance measurements at mildly polarizing
potentials, using a static mercury electrode in aqueous alkali metal chlorides at neutral and alkaline pH, exhibit
Mott-Schottky plots showing both p-type and n-type semiconduction depending on the frequency. There are also unique
differences in the nature of complex plane plots and Bode plots for different alkali metal ions, and these provide
clues to the ion-solvent interactions near the electrode surface. At sufficiently positive potentials Hg2CI2 and
an electron are produced by a charge transfer reaction. The dual semiconduction behavior may be due to the unique
disproportionation properties of the mercurous ion to produce different double layers. Formation of inner oxide
and outer hydroxide passive layers has been suggested by others to explain the dulex semiconducting behavior of
Fe-18Cr alloy in neutral and acid solutions.
|
Article - K
|
Modulation of Impedance
in DNA Solutions by Ions and Molecules: 1. Effect of Alkali Metal Ions
(Krishnan and Garnett, 204th Meeting of Electrochemical Society, Abstract 1378, Orlando 2003)
C.V.Krishnan, and Merrill Garnett
Garnett McKeen Lab, Inc.
150 Islip Ave, Suite 6, Islip, NY 11751 USA
This is the first part of a series of impedance measurements
of DNA solutions in the presence of different solutes such as alkali and alkaline earth metal ions, mono, di-,
and tri- alkyl substituted ammonium ions, tetraalkylammonium ions, tetraphenyl phosphonium, arsonium and boride
ions, alkyl sulfonates, aliphatic alcohols, and biological molecules such as hyaluronic acid, prothrombin, and
biotin in order to elucidate the process of electron transfer mechanisms in biological systems in terms of electronic
equivalent circuitry. The comprehensive list of ions and molecules is intended to provide information on solute-solute,
solute solvent, and solvent-solvent interactions near the electrode surface. These include effect of hydration,
water structure breaking, multiple hydrogen bonding, hydrophobic and πbonding (in both positive and negative
ions) interactions, and specific interactions.
The electrochemical analysis of nucleic acids at very low concentrations and at negative potentials of the mercury
electrode is elegantly summarized recently(1). Our measurements are at fairly large concentrations of DNA in order
to achieve packing of DNA and at slightly positive potentials of the mercury electrode in order to produce a dopant
mercury ion. Our recent impedance measurements of palladium lipoic acid complex using a mercury electrode at slightly
positive potentials reveal a complex electronic equivalent circuitry indicative of the complex packing of the molecule
serving as a semiconductor and the dopant coming from the mercury electrode(2,3). This had a catalytic effect on
our long term interest of developing electronic pathways in biological systems and implications for energy based
restorative medicine.
The impedance measurements of 0.01M solutions of Li+to Cs+chlorides at pH 6.0-7.0 and of NaCl in alkaline pH exhibited
unique Mott-Schottky plots indicative of both p-type and n-type semiconducting behavior of mercury electrode at
slightly positive potentials(4). Using these concentrations as background electrolytes, impedance measurements
of calf thymus DNA, 5 mg/mL at near neutral pH were carried out using a static dropping mercury electrode. To understand
the influence of chloride, measurement of DNA solution was also done without any alkali halide.
Figure 1 shows the Mott-Schottky plots and Figure 2 shows the complex plane plots of DNA terminating at 5 mHz.,
in the presence of 0.01M Li+, Na+, and K+chlorides. The observed zonal behavior can be explained in terms of contributions
from ion-solvent interactions and the interaction of the ions with the phosphate in DNA.
References:
1. E. Palecek, M. Fojta, F. Jelen, and V. Vetterl in Bioelectrochemistry, Vol 9, Chapter 12, 365, Edited by George
S. Wilson, Wiley-VCH,Weinheim, 2002
2. C.V.Krishnan and Merrill Garnett, 1stSpring Meeting of the International Society of Electrochemistry, Alicante,
Spain, 2003, Abstract P06
3. C.V.Krishnan, M. Garnett, and J. L.Remo, 203rdMeeting of ECS, Paris 2003, Abstract 2703
4. C.V.Krishnan and M.Garnett, 226thMeeting of American Chemical Society, New York 2003, Abstract 670792
|
|
|
|
