SYMPOSIUM ON COHERENT EXCITATIONS IN BIOLOGICAL SYSTEMS:
SOME IMPRESSIONS AND CONCLUSIONS

[Coherent Excitations in Biological Systems. / Ed. H.Froelich and F.Kremer.
Springer−Verlag, Berlin Heidelberg New York Tokyo, 1983, p. 222−224]

H.P. Schwan

Department of Bioengineering, University of Pennsylvania/D3, Philadelphia, PA 19104, USA

Some 40 scientists with background in the physical and biological sciences met from November 29 to December 1 in Bad Neuenahr, West Germany in order to discuss coherent excitations in biological systems and related topics. Field induced force effects, known as pondermotoric effects, and their biological manifestations were also considered. In addition several papers were offered on such topics as biological structure, metastable states in proteins, intracellular water, mm and sub-ram wave spectroscopy Most of these papers are included in this volume. I shall therefore not attempt to summarize them, but rather limit myself to comment only on a few and draw some general conclusions. The presentations were limited to twelve papers. This and the effective chairmanship of Froehlich assured room for valuable discussions and interactions.

Evidence for highly frequency specific biological effects of nun-waves had been presented several times during the past decade.

The Russian reports from the Puchinov Biophysics institute of the USSR Adademy of Sciences were never published in detail and Webb's results had been debated on technical grounds.

First detailed reports of highly frequency dependant growth of yeast cells were then published by Grundler and Keilmann. But their mm-wave applicator was complex and defied analysis of the specific absorption rate (SAK) in the test solution. Grundler has since then introduced a superior radiator. He presented his new results. There were three highlights in his presentation.

- First, very detailed data with more points then ever before demonstrated highly frequency dependant growth effects.

- Second, the new results confirm the results with the earlier radiating device.

- Third, observations on single cells and their response to the field also indicate high frequency specificity. The extension of his new technique of single cell observation appears promising.

Motzkin from the Polytechnical Institute of New York briefly summarized her results, using different techniques and materials. She has so far not been able to observe frequency specificity.

Nor has the Utah group headed by O.Gandhi which published their results in detail about a year ago. But Gandhi et al. obtained biological responses at 0.5 GHZ intervals, while Grundler's results require resolution better than 10 MHZ.

Others should try to duplicate Grundler's results, using the same technique and biological endpoint. Until this is done, some will continue to debate the significance of Grundler's results. If high frequency specificity will be accepted beyond doubt, Froehlich's theory of coherent excitation in the mm-wave region will probably account for such results. The implications to biophysical research are then no doubt enormous even though at the moment unpredictable.

Some other papers in this category of mm-wave effects were presented by Kremer and Genzel. Kremer observed non-thermal effects of mm-wave radiation on giant chromosomes. Since his frequency was swept between 64 and 69 GHz, high frequency specificity is not necessarily indicated. Genzel and coworkers studied the dynamics of large biomolecules from 50 to 150 Ghz and in the range of 20 to 480 wavenumbers per cm over an extended temperature range. Strong absorption peaks were observed and a relaxation model proposed. But, as Genzel stated, these phenomena will probably not take place if biomolecules in an aqueous medium are used because of the strong absorption of liquid water.

Hasted also presented absorption data in the 10 to 550 cm ⁻¹ range. Proteins, polysaccharides and amino acids were investigated. The data demonstrated that absorption features of the more complex proteins can be composed at least in part from those of their subunits. Furthermore it appears that hydrogen bond vibration fundamentals and their harmonics are involved.

Hasted presented evidence for the existence of metastable states in proteins. The existence of such metastable states have been suggested by Froehlich. Hasted demonstrated that the dielectric properties of hemoglobin films consisting of 3 to 7 molecular layers display relaxation effects below some Hertz which are strongly dependant on the applied field strength of some MV/m. Such field strength values exist in biological membranes. Properties acquired under the influence of the applied field return slowly over weeks to the original level. This writer mentioned at the meeting that electrode polarization processes might participate in the- low frequency relaxation process. But it appears on closer examination of the data provided by Dr. Hasted that this is less likely than originally anticipated.

Clegg presented a detailed summary of cytoplasmic organelles and the cytoskeleton discovered only in recent years. He estimated the surface area of all such structures in a cell. Assuming structured water to extend up to 100 or 150° from the surface he concluded that most water inside cells ought to be different from normal water. However if one assumes bound water to be restricted to a few molecular layers the usual amounts of bound water would probably be arrived at.

The last half day of the meeting was largely devoted to field induced forces and their biological manifestations. These pondermedoric effects can cause many biological responses, are of a non-thermal nature and also frequency dependant, even though this dependence is not as sharp as anticipated by Froehlich theory of mm-wave interactions with bio-systems.

Pohl, who studies extensively the movement of particles and cells in non-uniform alternating electrical fields, gave an excellent summary of it.

Zimmermann, known for his past work on the breakdown of membranes under electrical stress, has concerned himself in more recent years with a variety of cellular responses to alternating and pulsed fields. He gave a stimulating presentation and demonstrated how useful the study of these effects is for a variety of purposes.

Sauer presented a paper summarizing his derivation for the force acting on a particle exposed to an alternating electrical field and the trajectory of a particle approaching another one. The force equation was derived for the general case that both particle and medium have complex permittivity, thereby extending previous equations for the pure dielectric case. This finally should put to rest a longstanding debate what equations to use in the complex case.

Biological interaction mechanism of electromagnetic radiation whose quantum energy is far too low to form radicals has been of increasing interest during the past two decades. Froehlich proposed more than a decade ago that biological reactions to non-ionizing radiation are likely to be nonlinear and highly frequency specific. Indeed if such interactions were linear then the strong absorbance of water would prevent a resonant response. So far it has not been possible to demonstrate specific sites at the cellular or macromolecular level which could be responsive. Suggestions include biological membranes, biological macromolecules, the intracellular cytoskeleton, structured water near macromolecular surfaces. The papers in this volume contribute to the debate even though they can not pinpoint yet a specific interaction site. They contain valuable material likely to influence future research.

The meeting was well organized and supported financially by IBM Deutschland GmbH Stuttgart. It took place in a pleasant well known West German spa and facilities were excellent. Thanks are due to IBM and Professor Froehlich for making this meeting possible.