Dear Shorabi, it seems to me a way to complicate your analysis. There are dozens of method to analyze VOCs by GC-MS, so why do you want to use HPLC-MS? Probably you can still detect some organic compounds with HPLC-MS, but to validate your analysis you should compare the new method with an accepted one. HPLC-MS has been optimized to remove the solvent before the MS detection, so you will loose most of your analytes, moreover several VOCs are not easily ionizable by simple ES ionization.
Dear Shorabi, it seems to me a way to complicate your analysis. There are dozens of method to analyze VOCs by GC-MS, so why do you want to use HPLC-MS? Probably you can still detect some organic compounds with HPLC-MS, but to validate your analysis you should compare the new method with an accepted one. HPLC-MS has been optimized to remove the solvent before the MS detection, so you will loose most of your analytes, moreover several VOCs are not easily ionizable by simple ES ionization.
If by VOC's you mean compounds on the EPA list for method 8260 (mostly small aromatics and small halogenated alkanes), you will have difficulty. The aromatics might work if you are fortunate enough to have a photionization detector or the detector Divya mentioned available. Retention and separation of such small molecules may be tricky. Massimo's question of why bother is one you should think carefully about whether it is worth the time to try,
There is an overlap between the compounds that can be analyzed by GC-MS and LC-MS, and not all "VOCs" exclusively fall into one or other category. If you want a picture that is as comprehensive as possible you might want to try both; if you are looking at certain compounds classes of interest I would suggest to go through recent literature. Over the last 4-5 years, a number of GC-MS applications have been ported to LC/MS successfully as LC/MS is just the more recently implemented method in many routine laboratories. However newer is not necessarily better - I am with Massimo and Mark on this point.
Although it is possible to have a hplc method for specific VOCs (a major overtaking by the way) it is almost impossible to have a good screening method for variety of (unknown) solvents.
There are VOCs with very low limits, such as benzene with limit of 2 ppm, which will be almost impossible to detect because it will be dilluted in the MF and in the column, and most importantly, the ESI ionization efficiency is only about 0,1%-the remaining 99,9% of the analytes are wasted in the surroundings.
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