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Determination of single biomolecules

  1. Apr 3, 2013 #1
    how to determine (theoretical, based on physics principles of detection of different fields from molecules without outside influence) individual electromagnetic field from single molecule for example dna, rna, different proteins, carbohydrates, fats etc.
  2. jcsd
  3. Apr 3, 2013 #2
    If by electromagnetic field you mean light, then you can tag these molecules with a fluorophore and detect that as a surrogate.
  4. Apr 3, 2013 #3
    There are different types of optical spectroscopy. Absorption, photoluminescence, and Raman scattering are all useful ways to study these molecules. Optical spectroscopy works at visible, infrared and ultraviolet frequencies. Most of these spectroscopies work with far field effects, which means electromagnetic waves.

    There are different spectroscopies that work at radio frequencies. Nuclear magnetic resonance and electron magnetic resonance use oscillating magnetic fields at radio frequencies. Most of these spectroscopies work under near field conditions. This means that the electromagnetic field in these spectroscopies are not true waves.

    Electrochemical methods are also used to separate molecules when they are ionized. This is a bit of a static field measurement.
  5. Apr 13, 2013 #4
    I think X-ray crystallography? Or NMR but probably xray. it has to do with determining electron density. and there are a bunch of functions like coulombs law i think and something called the electrostatic constant that can be used that's needed for coulombs law to map isopotential lines.
  6. Apr 13, 2013 #5
    Xray crystallography can be used to determine the positions of atoms in the molecule, and the distribution of electrons around the nucleus of the atom. This is related to the "electromagnetic field" in the molecule.

    There have been a lot of suggestions. The OP hasn't responded to any of them. It leads me to think that we don't know what he means by an "electromagnetic field". His concept of electromagnetic field may not be the same as what a scientist usually means by "electromagnetic field".

    I think that we should wait with the suggestions until the OP gives us a better idea of what he is asking.
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