Bioelectrodynamics

Plenty of theoretical work was published on theories and hypotheses describing generation of electromagnetic field by living cells in very broad frequency range.{{cite journal | last1=Priel | first1=Avner | last2=Tuszynski | first2=Jack A. | last3=Cantiello | first3=Horacio F. | title=Electrodynamic Signaling by the Dendritic Cytoskeleton: Toward an Intracellular Information Processing Model | journal=Electromagnetic Biology and Medicine | publisher=Informa UK Limited | volume=24 | issue=3 | year=2005 | issn=1536-8378 | doi=10.1080/15368370500379590 | pages=221–231| s2cid=83894290 }}{{cite journal | last=Cifra | first=M. | title=Electrodynamic eigenmodes in cellular morphology | journal=Biosystems | publisher=Elsevier BV | volume=109 | issue=3 | year=2012 | issn=0303-2647 | doi=10.1016/j.biosystems.2012.06.003 | pages=356–366| pmid=22750075 }}{{cite journal | last1=Zhou | first1=Shu-Ang | last2=Uesaka | first2=Mitsuru | title=Bioelectrodynamics in living organisms | journal=International Journal of Engineering Science | publisher=Elsevier BV | volume=44 | issue=1–2 | year=2006 | issn=0020-7225 | doi=10.1016/j.ijengsci.2005.11.001 | pages=67–92}} The most influential one was once probably the Fröhlich's hypothesis of coherence in biological systems introduced by Herbert Fröhlich in the late 1960s.GJ Hyland and Peter Rowlands (editors) Herbert Frohlich FRS: A Physicist Ahead of his Time. (University of Liverpool, 2006, 2nd edition 2008.) {{ISBN|978-0-906370-57-5}} Despite the fact that experimental evidence for Fröhlich's hypothesis does not exist yet, numerical estimates indicate biological feasibility of at least Fröhlich's weak condensation.{{cite journal | last1=Reimers | first1=J. R. | last2=McKemmish | first2=L. K. | last3=McKenzie | first3=R. H. | last4=Mark | first4=A. E. | last5=Hush | first5=N. S. | title=Weak, strong, and coherent regimes of Frohlich condensation and their applications to terahertz medicine and quantum consciousness | journal=Proceedings of the National Academy of Sciences | volume=106 | issue=11 | date=26 February 2009 | issn=0027-8424 | doi=10.1073/pnas.0806273106 | pages=4219–4224|doi-access=free | pmid=19251667 | pmc=2657444| bibcode=2009PNAS..106.4219R }}

Recent theoretical considerations predict generation of radio frequency electromagnetic field in cells as a result of vibrations of electrically polar intracellular structures, e. g., microtubules.{{cite journal | last1=Pokorný | first1=Jiří | last2=Hašek | first2=Jiří | last3=Jelínek | first3=František | title=Electromagnetic Field of Microtubules: Effects on Transfer of Mass Particles and Electrons | journal=Journal of Biological Physics | publisher=Springer Science and Business Media LLC | volume=31 | issue=3–4 | year=2005 | issn=0092-0606 | doi=10.1007/s10867-005-1286-1 | pages=501–514| pmc=3456341 | pmid=23345914 }} Emission in optical part of electromagnetic spectrum is usually attributed to reactive oxygen species (ROS).

Bioelectrodynamic effects were experimentally proven in optical range of electromagnetic spectrum.{{cite journal | vauthors = Kučera O, Červinková K, Nerudová M, Cifra M | title = Spectral Perspective on the Electromagnetic Activity of Cells | journal = Current Topics in Medicinal Chemistry | volume = 15 | pages = 513–522 | date = 2015 | issue = 6 | pmid = 25714382 | doi = 10.2174/1568026615666150225103105 }} Spontaneous emission of photons by living cells, with intensity significantly higher than corresponds to emission by thermal radiation, was repeatedly reported by several authors over decades.{{cite journal | last1=Cifra | first1=Michal | last2=Fields | first2=Jeremy Z. | last3=Farhadi | first3=Ashkan | title=Electromagnetic cellular interactions | journal=Progress in Biophysics and Molecular Biology | publisher=Elsevier BV | volume=105 | issue=3 | year=2011 | issn=0079-6107 | doi=10.1016/j.pbiomolbio.2010.07.003 | pages=223–246 | pmid=20674588}} These observations exhibit experimental simplicity and good reproducibility. Although non-thermal emission of photons from living cells is generally accepted phenomenon, much less is known about its origin and properties. On the one hand, it is sometimes attributed to chemiluminescent metabolic reactions (including for instance reactive oxygen species (ROS) {{cite journal | last1=Prasad | first1=Ankush | last2=Pospišil | first2=Pavel | title=Two-dimensional imaging of spontaneous ultra-weak photon emission from the human skin: role of reactive oxygen species | journal=Journal of Biophotonics | publisher=Wiley | volume=4 | issue=11–12 | date=20 October 2011 | issn=1864-063X | doi=10.1002/jbio.201100073 | pages=840–849| pmid=22012922 }} ), on the other hand, some authors relate this phenomenon to far-from-equilibrium thermodynamics.{{citation needed|date=November 2012}}

Indirect evidence exists on acoustic and radio frequencies; however, direct measurement of field quantities is missing. Pohl and others observed force effect on dielectric particles which were attracted to cells and repulsed from cells, respectively, depending on particles' dielectric constant.{{cite journal | last1=Pohl | first1=Herbert A. | last2=Crane | first2=Joe S. | title=Dielectrophoresis of Cells | journal=Biophysical Journal | publisher=Elsevier BV | volume=11 | issue=9 | year=1971 | issn=0006-3495 | doi=10.1016/s0006-3495(71)86249-5 | pages=711–727| pmid=5132497 | pmc=1484049 | bibcode=1971BpJ....11..711P |doi-access=free}} Pohl attributed this behavior to dielectrophoresis caused by electromagnetic field of cells. He estimated the frequency of this field as about hundreds of MHz. Other indirect evidence comes from the fact that mechanical vibrations were experimentally proven in very broad frequency range in cells.{{cite journal | last1=Kruse | first1=Karsten | last2=Jülicher | first2=Frank | title=Oscillations in cell biology | journal=Current Opinion in Cell Biology | publisher=Elsevier BV | volume=17 | issue=1 | year=2005 | issn=0955-0674 | doi=10.1016/j.ceb.2004.12.007 | pages=20–26}} Since many structures in cells are electrically polar, they will generate electromagnetic field if they vibrate.{{cite journal | last1=Kučera | first1=Ondřej | last2=Havelka | first2=Daniel | title=Mechano-electrical vibrations of microtubules—Link to subcellular morphology | journal=Biosystems | publisher=Elsevier BV | volume=109 | issue=3 | year=2012 | issn=0303-2647 | doi=10.1016/j.biosystems.2012.04.009 | pages=346–355| pmid=22575306 }}

As a question opened for decades, bioelectrodynamics was not always part of scientific mainstream and thus it was sometimes treated with poor scientific standards. This is particularly true for:

1. - overestimation of the significance of experimental data obtained (Kucera{{cite journal | last1=Kučera | first1=Ondřej | last2=Cifra | first2=Michal | last3=Pokorný | first3=Jiří | title=Technical aspects of measurement of cellular electromagnetic activity | journal=European Biophysics Journal | publisher=Springer Science and Business Media LLC | volume=39 | issue=10 | date=20 March 2010 | issn=0175-7571 | doi=10.1007/s00249-010-0597-8 | pages=1465–1470| pmid=20306029 | s2cid=36245681 }} argues that claims by several authors about direct measurement of cellular electromagnetic activity in radio-frequency band should be accepted with skepticism since technical properties of experimental setups have not even met criteria arising from optimistic theoretical biophysical predictions. Firstly, spatial resolution of used sensors was too low with respect to expected spatial complexity of electromagnetic field in cells. Secondly, the sensitivity of experimental setups was not high enough compared to power available in living cell.),
2. - misinterpretation of experimental data (Fritz-Albert Popp's claim about coherence of photo-emission from cellsPopp FA (1999) [http://www.stealthskater.com/Documents/Consciousness_31.pdf About the Coherence of Biophotons 1999] Proceedings of an International Conference on Macroscopic Quantum Coherence, Boston University. is based on statistical distribution of photon counts; however, this is not proof of coherence. Coherent emission (see coherent states) has Poisson distribution, but Poisson distribution is not exclusively related only to coherent processes.) and
3. - development of uncorroborated hypotheses .{{citation needed|date=November 2012}}

• Medical physics
• Bioelectromagnetism

{{Reflist}}

• [http://bioed.ufe.cz/ Bioelectrodynamics research team, Institute of Photonics and Electronics of the Czech Academy of Sciences, Czech Republic]

Category:Bioelectromagnetics

Category:Electrodynamics