Ejecting chemical species from a sample using an electron beam

[samlat]

Hello,

I was wondering if it would be possible to eject chemical compounds from a sample, say like a biological tissue, using an electron beam. I know that electron scattering is one product of electron-specimen interaction, and that's the principle behind electron microscopy, but I'm more interested in material ejection from the sample.

Thanks!

 

[f95toli]

This is sort-of used all the time to deposit e.g. thin films of metals. However, all that happens is that the electron beams cause the metals to into a gaseous phase; the electrons are far too light to impart much kinetic energy.
Also, I doubt more complicated compounds could be used since the e-beam tends to heat (in case of metals melt). There are other ways to "eject" material from sample which is -relatively speaking- more gentle. See e.g pulsed laser deposition.

 

[sophiecentaur]

Mass spectrometry does what you describe to some extent. The snag when tissue is involved is to separate the various compounds from the tissue without changing them.
I have no idea of the advanced ways of doing it but it would involve chopping up and then using different solvents. An electron beam will knock molecules off and charge them. That allow the mass spec process. An external E field and a B deflecting field. Fragile molecules would best be separated with chromatography.