I am using the standard in the form of mixture i.e EPA VOC Mix 2 (2000 microgram per ml each component in methanol). As mentioned in COA, it is having 14 components / analytes. When this particular mixture was run on HPLC, it did not give all 14 peaks of different components. It gave only one broader peak with some minute peaks. The mobile phase utilized was Acetonitrile : Deionized Water. Why separate peaks were not being identified? What should be done / Which parameter of HPLC should be altered so that separate peaks could be identified?
Could you list the components in the EPA VOC Mix 2? When I did a google search I found a mix of aromates (BTEX) and some chlorinated and bromated benzenes, 12 components disolved in methanol. If this mix is the correct mix (or simlar) then it looks like a mix you would use for headspace analysis on a GCMS.
Can you tell us what sort of samples you want to analyze and in what matrix? What kind of detector is connected to the HPLC? Are you sure you should use a HPLC?
Please describe your problem better when you ask a question, there's not a lot of information we can use to give a usable answer.
Regards, Alex
Two answers already with absolutely no information to go on, I wonder.........nevermind.
I am not sure what the mixture is that you are asking about, but Sigma-Aldrich sells an "EPA VOC Mix 2" with 11 components. All EPA methods for VOCs use GC as the separation mechanism. Some VOCs may not be separated by your HPLC method. UV absorption can be very different for different compounds, so you will not see the same response for each compound, and compounds such as the halogenated methanes will not respond at all. The best method to use for VOCs in water is purge-and-trap GC with FID, ECD or MS as the detector, depending on what you want to detect and the detection limit that you need.
- Badges
- Science topic
- Similar topics
- Chemistry
- Organic Chemistry