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John McGinness



John Edward McGinness, PhD, MD, Pioneer in Organic electronics and Nanotechnology. B.S. Physics - University of Houston, 1966, PhD, Physics, Rice University, 1970, MD, University of Texas Medical School at Houston, 1985. Author of roughly 40 research publications, book chapters, and presentations.

Additional recommended knowledge

John McGinness pioneered much of the modern field of organic electronics.  

In 1972, while working at the Metallurgy department at Youngstown State University, Dr. McGinness suggested (1) that electronic conduction in melanins (polyacetylene, polypyrrole, and polyaniline "blacks" and their copolymers) is analogous to conduction in amorphous solids such as the chalcogenide glasses. This area was originally pioneered by Neville Mott, among others. That is, it involves such things as mobility gaps, phonon-assisted hopping, polarons, Quantum tunneling, and so forth. This report anticipated the later Nobel-prize-winning work of Shirakawa et al on conduction mechanisms in other oxidized polyacetylenes.

From Youngstown, Dr McGinness moved to the Physics Department of The University of Texas M. D. Anderson Cancer Center. The department had an interest in the physical properties of Melanin as a possible hook to treating melanoma. While of enormous importance now, this was a research backwater at the time. With the the notable exception of Bolto et al, who had reported [1] high conductivity in iodine-doped polypyrrole, few but melanoma researchers had much reason to look at the electronic properties of such rigid-backbone polymer "blacks". This is why the putative first molecular electronic device came from a cancer hospital.

The chalcogenide glasses show "switching", in which an applied "threshold voltage" reversibly switches a material from a low-conductivity "OFF" state to a high-conductivity "ON' state. The similarity of conduction mechanisms suggested that the melanins might also demonstrate voltage-controlled switching. Following this lead, Dr McGinness and his MD Anderson coworkers constructed a voltage-controlled switch incorporating melanin as its active element (2). They also further characterized its electronic behavior (3-8).

This device was a "proof of concept" for Dr McGinness' model for electronic conduction in such materials (1). In many ways, this work directly anticipated that leading to the 2000 Noble prize in Chemistry "For the Discovery and Development of Conductive Polymers", but with some differences. First, Dr McGinness built an actual device with a high conductivity "ON" state, while they looked at passive high conductivity in another of the same class of polymer. Similarly, the Nobel winners worked in reverse-- they stumbled upon passive high conductivity in another oxidized polyacetylene, unknowingly repeating the work of Bolto et al [2] with similarly iodine-doped polypyrrole. They then developed a model to explain high conductivity in such materials. This model was rather similar to Dr McGinness', with the addition of solitons for the special case of pure polyacetylene.

The pictured device represents several putative "firsts" in organic electronics. E.g., this voltage-controlled switch is apparently the first identifiable "active" organic semiconductor device. (An active device is one in which a current or voltage controls current flow.) As such, it is arguably parent to many later developments in organic electronics. In fact, only in the last decade or so have similar devices reappeared. Moreover, organic electronics is part of Nanotechnology. So this gadget is the putative first nanotech device. As such, it is now in the Smithsonians Institution's National Museum of American History collection of early electronic devices.

Similarly, while high-conductivity had been observed decades before in Charge transfer complex-type organic semiconductors and in polypyrrole [3], the "ON" state of the pictured device was the demonstration of a high "metallic" conductivity state in the linear-backbone conductive polymers. Thus, a subsequent news article in the journal Nature makes much of this materials "strikingly large conductivity", "high conductivity", and "large conduction".

At present, such oxidized polyacetylenes and their derivatives are the most commonly-used commercial conductive polymers. Further, the pictured device exhibited negative differential resistance (9), now a well-recognized property of electronically-active conductive polymers.

Interestingly, For further perspective concerning where this device fits in the history of Organic Electronics, see reference 9. A sample quote:

  • "Also in 1974 came the first experimental demonstration of an operating molecular electronic device (emphasis-added) that functions along the lines of the biopolymer conduction ideas of Szent-Gyorgi. This advance was made by McGinness, Corry, and Proctor who examined conduction through artificial and biological melanin oligomers. They observed semiconductor properties of the organic material and demonstrated strong negative differential resistance, a hallmark of modern advances in molecular electronics.58 Like many early advances, the significance of the results obtained was not fully appreciated until decades later...(p 14)"

Since he was at a cancer research institute, Dr McGinness' other interests included the role of free radicals in the action and toxicity of the anticancer drugs cisplatin, adriamycin, and bleomycin. E.g., he was the first to show (10) that the kidney toxicity of cisplatin involves reactive oxygen species. Some of this work was done with Harry Demopoulos, famous as the doctor in Clint Eastwood's Dirty Harry movies and as the person who resolved the Doris Duke will dispute. Dr McGinness was also involved in the dielectic spectroscopy of water bound to membranes. This was related to the future development of Magnetic Resoance Imaging

John and his coworkers also obtained two US patents for organic-polymer-based energy storge devices (batteries),US patents# #4,366,216 and #4,504,557


Some Publications

1) McGinness, J.E., Mobility gaps: a mechanism for band gaps in melanins Science. 1972 Sep 8;177(52):896-7.

2) McGinness, J.E., Corry, P.M., and Proctor, P.: Amorphous semiconductor switching in melanins. Science 183:853-855, 1974.

3) Mizutani, U., Massalski, T., McGinness, J.E., and Corry, P.: Anomalous low temperature specific heat results in melanins and intact melanosomes. Nature 259:505, 1976.

4) Filatovs, J., McGinness, J.E., Corry, P.M.: Thermal and electronic contributions to switching in melanins. Biopolymers 15:2309-2313, 1976.

5) Kono, R. and McGinness, J.E.: Anomalous Absorption and Sound in DBA Melanins. J. Applied Physics, 50(3): 1236-1244, 1979.

6) McGinness, J.E., Crippa, P.R., Kirkpatrick, D.S., and Proctor, P.M.: Reversible and Irreversible Changes in Hydrogen Ion Titration Curves of Melanins. Physiol. Chem. and Phvs. 11:217-223, 1979.

7) Filatovs, G.J., McGinness, J.E., Williams, L.: Statistical Analysis of Switching Melanins. Physicol. Chem. and Phys. Vol. 12, No. 5, 1980.

8) Kirkpatrick, D.S., McGinness, J.E., Moorhead, W.D., Corry, P.M., and Proctor, P.H.: Melanin-Water-Ion Dielectric Interaction. Pigment Cell Vol. 4p. 257-262, Karger Basel, 1979.

9) "An Overview of the First Half-Century of Molecular Electronics" by Noel S. Hush, Ann. N.Y. Acad. Sci. 1006: 1–20 (2003).

10) McGinness JE, Proctor PH, Harry Demopoulos, Hokanson JA, Kirkpatrick DS. Amelioration of cis-platinum nephrotoxicity by orgotein (superoxide dismutase). Physiol Chem Phys. 1978;10(3):267-77. abstract

11) John McGinness, Proctor, P.H., Harry Demopoulos, Hokansen, J.A. and Van,N.T. In vivo evidence for superoxide and peroxide production by adriamycin and cis-platinum. In: Pathology of Oxygen. A. Autor, (Ed.). Academic Press, New York, 1982, pp. 191-202.

12) McGinness J, Kishimoto A, Hollister LE. Avoiding neurotoxicity with lithium-carbamazepine combinations. Psychopharmacol Bull. 1990;26(2):181-4.

13) McGinness JE, Grossie B Jr, Proctor PH, Benjamin RS, Gulati OP, Hokanson JA. Effect of dose schedule of vitamin E and hydroxethylruticide on intestinal toxicity induced by adriamycin. Physiol Chem Phys Med NMR. 1986;18(1):17-24.

14) McGinness J. A new view of pigmented neurons. J Theor Biol. 1985 Aug 7;115(3):475-6.

15) Gulati OP, Nordmann H, Aellig A, Maignan MF, McGinness J. Protective effects of O-(beta-hydroxyethyl)-rutosides (HR) against adriamycin-induced toxicity in rats. Arch Int Pharmacodyn Ther. 1985 Feb;273(2):323-34.

16) Schrauzer GN, McGinness JE, Ishmael D, Bell LJ. Alcoholism and cancer. I. Effects of long-term exposure to alcohol on spontaneous mammary adenocarcinoma and prolactin levels in C3H/St mice. J Stud Alcohol. 1979 Mar;40(3):240-6.

17) Pietronigro DD, McGinness JE, Koren MJ, Crippa R, Seligman ML, Harry Demopoulos. Spontaneous generation of adriamycin semiquinone radicals at physiologic pH. Physiol Chem Phys. 1979;11(5):405-14.

18) McGinness JE, Crippa PR, Kirkpatrick DS, Proctor PH. Reversible and irreversible changes in hydrogen ion titration curves of melanins. Physiol Chem Phys. 1979;11(3):217-23.

19) Kirkpatrick DS, McGinness JE, Moorhead WD, Corry PM, Proctor PH. High-frequency dielectric spectroscopy of concentrated membrane suspensions. Biophys J. 1978 Oct;24(1):243-5.

 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "John_McGinness". A list of authors is available in Wikipedia.
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