Chromatography Forum

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How about this; http://www.avivanalytical.com/ChromatoProbe.aspx ?

Peter

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Never heard of Chromatoprobe. Here's a more concise and in my opinion clearer explanation of how it works:

https://www.agilent.com/cs/library/data ... obe_ds.pdf

Hi

I have seen this before and met Professor Aviv Amirav, the Chromatoprobe developer. Out of interest he also developed the Pulsed Flame Photometric Detector (PFPD)

I have played with a similar technique of dropping a small glass u - tube ( can't remember where I obtained them) containing a solid sample into the injection port to desorb the volatiles.

What exactly is it that you wish to analyse for and in what matrix?

Regards

Ralph

Hi Peter,

Thanks for your response, this looks very interesting. Have you any experience with using it yourself?

Best wishes,

Joe

Hi Joe, no I've never used one. They were an off-the-shelf option with Varian GCs in the pre-takeover days, I couldn't find any reference to them on the
Bruker site.

Edit - the link that rb6banjo posted shows that Agilent kept them when it spun off the GC business to Bruker.

Peter

http://www.gerstel.com/en/gc-liner-exch ... mation.htm

If you used one of these, and load the sample into each injection port liner, it would be an automated way of doing this type of sampling.

I seem to remember someone actually used this autosampler but made sample tubes that were fritted on the bottom to hold samples. I just remember it years ago at Pittcon, but can not remember who it was that did it.

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Hi Joe

You are re-inventing the wheel - 30 years ago Brill, J.H. and Bertsch, W. published exactly this in J. High Resolut. Chromatogr. Chromatogr. Commun. 9: 462-464 and there have been dozens of variants on the theme since.

You need an inlet that you can cool and heat rapidly - you have to put the sample into the liner and seal it up while it is cold, purge all the air out with a rapid flow and high split ratio, then close the split and heat the inlet. I have done a similar thing with blobs of scent secretions from mammals and it works OK but cruds up the inlet in short order.

Peter

Hi Joe

Some useful comments from Peter.

I had many analyses that were just one offs and didn't justify the purchase of dedicated equipment.

When I tried solid sampling in a "crude" manual way just like this I found liquid CO2 cooling at the head of the column to be very beneficial in cryo-focusing the volatiles since my injection port didn't heat up that rapidly and I found that the desorption of the volatiles was relatively slow - enough to cause peak distortion.

I used this SGE version that was relatively cheap to purchase and easy to install but it does mean having access to a liquid CO2 cylinder.

http://www.sge.com/uploads/5a/8f/5a8fb7 ... 0044-A.pdf

Just a few further questions

1. What equipment do you have?
2. What are your expected analytes and the project outline of your PhD? Sounds interesting. Interestingly, along with bacteria and airborne moulds sometimes mites are beneficial in the development of flavours in cheese - sorry, just threw that in after just having been on a cheese making course
3. You say that you have had problems with the chromatography by solvent extraction - what were they? Was it a micro-scale extraction? Were the mites freeze dried/crushed?
4. Can you post a link to literature reference(s) that you mentioned?

Regards

Ralph

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Hi Joe

With all due respect I and others are trying to help you

It would be helpful to me to answer

1. ?
2. ?
3. ?
4. ?


Kind Regards
Ralph