Advice HPLC vs GC Triple quad analysis

[Ruben]

Hi I am looking to analyse the following groups of compounds :

1. chlorinated pesticides

2. PCBs(either as Arochlor 1260 or as isomers)

3. PAHs

4. Organophosphate compounds

5. Pharmacheuticals

6. EDCs

7.Volatiles(BTEX)

8.TPHs

9. Brominated flame retardants

10. Dioxins

11. Linear alkyl benzenes

12. Chlorinated paraffins.

13. Organotins

I will be targeting water, soil/sediment and biological tissue samples.

Please can anyone assist with a comparison of the best technique of analysis(either GC/MS or HPLC/MS). If it can be done on both please indicate. Can you also provide LOD and LOQ values for each technique.

Additionally, can you also indicate if any special sample prep equipment is needed? eg. cleanup/removal of lipids, filteration equipment etc.

Thank you

Ruben

[Ron]

Most of these can be done by GCMS. There are US EPA methods that you can access on-line for many of these classes of compounds. Check these methods for conditions and detection limits.

Pharmaceuticals is a very broad category, but in general these are polar compounds that are more suited to LC in the native form. Many can also be done by GC, but you may have to form a derivative to get through the column.

There is a lot of information on the web on existing methods to do these compounds, and if you seach this forum many of these have already been discussed.

[tima]

Demanding request.... I would say you need to go to the EPA web site and do some research yourselve. Make up a spreadsheet with LOD, LOQ, etc. when you go through all their methods and I think you will have a better handle on the types of analysis and the type of instrumentation that you require to do that full list of components. I think you'll conclude that having both types of instrumentation is what is needed.

As far as I know, the volatiles are only done by GC/MS, GC/FID or GC-ECD so there is one major limitation of LC/MS. The pharmaceuticals and ECD's have well documented methods (EPA as well) for LC/MS/MS. Good luck with it. Timothy

[tima]

Demanding request.... I would say you need to go to the EPA web site and do some research yourselve. Make up a spreadsheet with LOD, LOQ, etc. when you go through all their methods and I think you will have a better handle on the types of analysis and the type of instrumentation that you require to do that full list of components. I think you'll conclude that having both types of instrumentation is what is needed.

As far as I know, the volatiles are only done by GC/MS, GC/FID or GC-ECD so there is one major limitation of LC/MS. The pharmaceuticals and ECD's have well documented methods (EPA as well) for LC/MS/MS. Good luck with it. Timothy

[CE Instruments]

You will almost certainly be best served by buying a laboratory
To run all those methods you will need several different set ups and just swapping between them means that you will need more than one instrument. Note if you really need to do Dioxins and identify them at the required levels you will require a High Resolution Sector MS system to add to at least a decent GC/MS and LC/MS/MS