Chromatography Forum

Is there anyone that has expercience with determination of genotoxic compounds with GC-FID / GC-HS-FID / GC-HS-MS or GC-MS ?

(eg CH3Br, C2H5Br, C3H7Br, C4H7BrO2, ...)

If your compounds are all Halogenated and you do not have GC/MS you should be looking at GC/ECD or if not all Halogenated the Thermo GC/ECD/FID as they can run ECD in series with FID.
GC/MS will be your choice if available for conformation. If you can get good recoveries for all compounds my choice would be headspace.
Perhaps Fred can advise see http://www.sepsci.com/chromforum/viewtopic.php?t=2151 as he is also interested in Genotoxics ?
Regards Richard

The ECD detector hqs been ordered but not yet arrived, same as Fred it is to determine these genotoxics in API's as far as 1 ppm or even lower.

I'll contact Fred for his experience so far..

Any other ideas are still welcome concerning sample prep or instrument settings cause the low respons of these compounds on HS as on MS

Hi,
I don't know about your compounds but about the ones I'm working on, headspace didn't work and of course trying with FID will probably waste your time. Even with my 5973N (simple quad, EI) it's pretty hard to be under 500ppb. Hope it'll answer to you questions

Any succes in using the ECD? Are there any special hints that you could share. The final goal would be in making a mixture of this genotoxic compounds and trying to have a validated general method method for quantification.

Any ideas ?

Sorry but we don't have ECD so I can't tell you about it...and no ideas

Yes! you can work with ECD, I did it once and the detection limit is very low, the adventage is that ECD is specific for hallogenated compounds,but you have to be sure what are you detecting, because those are very light gases, and for confirmation you should to use GC/MS, how are you proccesing your samples? SPME works very well!

Like i said, the ECD has been ordered. For the moment we are just working with a standard mixture of 1 solvent dissolved in DMI. But about sample prep didn't we look into yet. Have no experience with SPME.
can you share some of your experience about that ?

with GC/MS (single quad) we can go upto 10 ppm for detection, but working on that one too.

Tried an ECD somewhere else... but didn't get anything out of it for chromatography.

Tried a test solution of chloroform (2500ppm) in hexane, but only got very low respons.

What could there be wrong ?

I have not seen a complete list of analytes this thread addresses, but of the few listed initially, I suspect that in the presence of water the brominated analytes will react catalytically with any metal in the MS or in the HS.

If the analytes are volatile, limits of less than 100 ppb should be attainable. Several years ago I used a FID to detect chloroform in water and had a quantification limit of 25 ppb using headspace analysis. Since I had water in the matrix and did not have a multidimensional system to eliminate the water, I did not use an ECD.

Alternately, SMPE headspace should work quite well for the analysis of these brominated analytes, especially at very low levels. and will have an inert flow path that is required, in my opinion, to perform this analysis.