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Biophoton Emission Outside Visible Range

  1. Nov 26, 2014 #1
    There are a lot of florescent proteins in the visible range, but why haven't we fount any above or below that range?
    I think a protein that emits radio waves could be very helpful both biologically and scientifically. Are we not looking for such proteins, or do they not exist?
  2. jcsd
  3. Nov 26, 2014 #2

    jim mcnamara

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    Is this 'visible range' human or do we include other species?

    Here is a discussion of the evolution of the spectra of bioluminescent oragamisms:

    Marine organisms by far the most common bioluminescent species.
    Humans are trichromats - we use three pigments to perceive light, many marine species have more - fairy shrimp have 12.

    Lets assume that BL (bioluminescence) has some sort of advantage, and that it has to be perceived somewhere somehow by some mechanism to convey an advantage. Radio waves have looong wavelengths compared to UV->visible->near infared spectra. There are no simple organic pigment molecules that can pick up radio waves because the molecule is tiny compared to the wavlengths. Radio wavelengths are on the order of centimeters to meters, the near-visible wavelengths are in nanometers, on a scale with pigment molecules. Somebody here at PF can explain how antennas work, and no known organisms appear to have antennas capable of 'seeing' 20m radio waves.
  4. Nov 26, 2014 #3


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    Fluorescence comes about from the movement of electrons between electronic levels in an atom/molecule. The energy differences between these electronic levels correspond to light in the near IR to UV range, so fluorescence can only emit photons in this range. Significantly shorter wavelentghs of light are energetic enough to begin breaking chemical bonds, so they would not be practical in a biological system. Significantly longer wavelengths of light correspond to energies comparable to the thermal energy available in the environment, which would make detecting these wavelengths difficult (see this post for an extended explanation).
  5. Nov 27, 2014 #4
    Thank you both very much, those where incredibly helpful answers!

    It appears that this could not emerge biologically due to the receiving end... Do you think a voltage sensitive radio fluorescent protein could be engineered, or would it be over sensitive?
  6. Nov 27, 2014 #5
    Biophotons are not the same as bioluminescence. Biophotons are so so faint they can't be seen with the naked eye. You need photomultiplier tubes and 15-minute exposures. They are an incidental product of biochemical reactions in plants and animals. They are non-thermal, and involve both visible light and UV.

    Like the Schumann resonances, they have been hijacked by the pseudoscience people.
  7. Nov 27, 2014 #6
    Oh, my bad. I thought that it was just a general term for a photon released in a biological process. Thank you for clarifying that, I don't want to make that mistake again!
  8. Nov 28, 2014 #7


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    There are not that many chemical reactions which go in hand with the emission of radio waves. The only example I am aware of, is from CIDNP spectroscopy, where strong magnetic fields are required.
  9. Dec 2, 2014 #8
    I believe CIDNP causes emissions from the nucleus like MRI machines and NMR. So the emission isn't part of the natural process.
  10. Dec 3, 2014 #9


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    It is true that CIDNP is measured in NMR Spectrometers, usually. However, it does not require excitation by external radio fields but the radio frequency field generated is due to the chemical reaction taking place. The high magnetic fields required are admittedly not very physiological.
  11. Dec 3, 2014 #10
    Wow, that's still very cool!
  12. Dec 3, 2014 #11


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    I know that this isn't exactly within the confines of the intended subject matter, but wouldn't the discharge of an electric eel or ray emit RF frequencies?
  13. Dec 14, 2014 #12
    You are correct, electric discharge can release RF, which can be observed in lightning.
    However, I'm not sure electrocytes and neurons produce a strong enough discharge...
    On the other hand, if they are strong enough, then perhaps the studies of lightning could
    identify the frequencies emitted?
  14. Dec 14, 2014 #13


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    No. Ever seen a biological object creating a lightning flash? It just does not happen.

    They cannot.
  15. Dec 14, 2014 #14
    It's not just the amplitude but also the frequency. Electromagnetic waves don't become electromagnetic radiation until they are about two wavelengths away from the source. Until then they depend on the source for their energy. After two wavelengths they become self-propagating. That's also about where virtual photons turn into actual photons. The lower the frequency the more energy you need to sustain the waves until they can propagate by themselves. Sparks, on the other hand, generally produce radio waves.
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