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- Posts: 28
- Joined: Mon Nov 07, 2011 9:05 am
I am working on the determination of mineral Oil Hydrocarbons in complex food matrices, such as olives and Lima beans. Liquid extraction with hexane is used, with on-line epoxidation-HPLC-GC. A silica column is used to separate MOSH and MOAH, then the fractions are transferred to the GC.
The problem is that after a few injections, retention in HPLC begins to change, so I cannot fractionate correctly. I know this is a very complex matter to be discussed in a forum, however any feedback would be greatly appreciated.