At 10:36 AM 5/12/1999 +0200, you wrote:
>Hello everybody,
>
>I would like to measure the d15N of the aminoacids Arg and Gly (separately)
>in a mixture of several aminoacids, and possibly other nitrogeneous
>compounds. I guess this is possible with the GC-C-IRMS technique, but I
>have never used it.
>
>I would be very gratefull to anybody who could ask one or several of the
>following questions :
>
>- is it possible or do I have to purify Arg and Gly from my mixture before?

I have never done Arg, but some Gly. I usually use a more polar column like
a RTX-35 or a SuppelcoWax. Separation problems only occur, if the Ala peak
is much higher than the Gly peak.

>- what is the minimum amount of matter needed per measurement?

Try not to go under 1nmol and splitless injection.

>- who does this kind of analyses and how much does it cost?

n-acety-methyl derivative are good for Gly.

Good luck

Michael Haisch


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Michael Haisch                 [log in to unmask]
Clin. Pharmacology           Voice: 802-656-5065
University of Vermont         Fax:   802-656-1229
Burlington, VT 05405
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