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Icon 11 posted May 21, 2010 04:47      Profile for Ashitaka     Send New Private Message       Edit/Delete Post   Reply With Quote 
/ Bill Nye voice

So Floyd Landis admitted to taking dope and says "but all the other kids were doing it!" (paraphrasing)

But I don’t really care more than I think it is really cool how they test this.

The thing is, testosterone made by teh human body and testosterone made artificially, is the same thing, the same structure, the same orientation, the same "almost" everything.

lets start,

Carbon (C) is made up mostly of carbon 12 (ca 99%), and then carbon 13 (1%) as the two stable isotopes.

side notes:
-Isotopes have differing numbers of neutrons, and therefore have different masses.
-carbon 14 used for carbon dating, is not stable, that is why you can carbon date things.

So this 1 % C-13 is pretty normal in all non-organic forms of carbon, but because of the complex nature of plant respiration ( plants take in inorganic C02 from the atmosphere and use it to make organic molecules), the carbon 12 is more likely to be taken up that the C -13 so organinc carbon has less C-13 in it than non organic C-13.

basically the heavier carbon doesn’t react as well as the lighter carbon because it hits with to much momentum in molecular collisions inside the plants.

Since all higher life forms get their carbon from eating lower life forms, which at one point got their carbon from a plant, the higher you go up in the food chain, the less C-13 there is.

So, now on to the testosterone.

The chemical formula for the testosterone injected is identical to the chemical formula for artificially produced testosterone. SO how do you test if the testosterone in urine is produced by the body or is artificial? By comparing the isotope ratios of course.

The synthesis of artificial testosterone is not completely made using inorganic molecules. The reactants that they start with are a steroid backbone derived from plants. But there are enough steps, using carbon from non-plant sources, that synthetic testosterone has more C-13 than testosterone produced in the body.

Now, it should be mentioned that fast growing plants in the tropics refine the carbon much better than the slow growing sources in cold climates

Now, I think back four years ago when the charges were made they used the defense that if you consume carbon from slow growing organics sources the ratio analysis method does not work. This theory had never been tested and Landis got off.

Here is a bunch of cool things you can do with isotope ratios.

"If they're not gonna make a distinction between Muslims and violent extremists, then why should I take the time to distinguish between decent, fearful white people and racists?"

-Assif Mandvi

Posts: 3093 | From: Switzerland | Registered: Feb 2006  |  IP: Logged
BlabberMouth, a Blabber Odyssey
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Icon 1 posted May 21, 2010 08:00      Profile for littlefish   Author's Homepage     Send New Private Message       Edit/Delete Post   Reply With Quote 
There was someone at my old university who was researching the isotopic ratios to trace the origin of marijuana for the police. The other part of his PhD was watching concrete dry. Making concrete set under the extreme conditions found in oil well manufacture is more complicated than you might at first believe.

I'm sure I was told that there was more heavy C at the equator due to the centrifugal effect of the earth's spin. The same concept is used to purify uranium, but on a much smaller scale.

I'm about to start on some isotopically labelled experiments myself. You can buy pure(ish) carbon-13 compounds, react them, and see where the carbon ends up.

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BlabberMouth, a Blabber Odyssey
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Icon 1 posted May 21, 2010 10:51      Profile for TheMoMan         Edit/Delete Post   Reply With Quote 
____ Some times things taught defy logic, if the spin is that much more powerful at the Equator why is there water at the poles.

____ Ah yes Lutes and Concretes, spent two terms studing those buggers for making machine bases. One problem is making it thin enough to pump down to the well head, the other is to make it thick enough to block the pipe. Hey would Cholesteral work it sure plugs arteries. Now the additives that make it swell during curing have to be able to withstand the action of oil and not weaken the concrete at the same time. The oil companies will claim "we have done this before but not at this depth".

Those who would give up essential liberty to purchase a little temporary safety deserve neither liberty nor safety.

Benjamin Franklin,

Posts: 5855 | From: Just South of the Huron National Forest, in the water shed of the Rifle River | Registered: Sep 2002  |  IP: Logged

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