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Kevin wrote:

> Hi all,
>
> I have read in several places that water shouldn't be used as a
> solvent for GC especially when using capillary columns.  However other
> references seem to dispute this.  Is there a definitive answer to
> this.

..snip, snip

Hi,

you can do a direct injection of water in a GC  if you use a special
injector -
a programmed temperature vaporizer (PTV) injector
and a technique called: Large Volume Injection (LVI).

But indeed its a trick, because you
1) inject water in the GC injector
2) enrich the components on an adsorbent
3) dry the adsorbent
4) heat the adsorbent
5) and let this gas stream flow through the gc column.

There is a nice review giving a lot of references and also showing some
chromatograms obtained by direct water injection in GC from:

W. Engewald , J. Teske and J. Efer
Programmed temperature vaporisers-based large volume injection in
capillary gas chromatography
Journal of Chromatography A ; Volume 842, Issues 1-2 ; Pages 143-161

 http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=ScienceSearch&_method=citationSearch&_piikey=S0021967399000801&_returnURL=http://www.scirus.com&_version=1&md5=9e9a6e04098843a97110947a198d5059

or you can find a lot of other literature if you go to
http://www.scirus.com

and enter the words:  large volume injection   ptv
http://www.scirus.com/index.php?viewresults=yes&wordtype=all&query=large+volume+injection+++ptv+&docsource=dsall&saall=on#results

(I don't know if the robots will break these long links)

Some other good keywords are (all mixed together or alone)
* PTV - programmed temperature vaporisation
* PTV-  programmed temperature vaporization (yes some search engines have
no phonetic search :-(
* thermo desorption
* gas-phase adsorption
* SPE (Solid Phase Extraction), Tenax, cold-trap, cryo-trap
* ATAS , Gerstel , Varian , Agilent
* LVI - Large Volume Injection
* Programmable Temperature Vaporizing Injector
* PTV-GC-MS
* injection of aqueous samples

With kind regards from LE
Tobias Kind


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