Hi Asim,
do you understand VFA as volatile fatty acids? If so, then I would choose the GC as analysis technique (possibly with precolumn derivatization as methyl ester). Fatty acid analysis using GC is a tried and tested method of analysis. I would only use LC if the fatty acids cannot be evaporated at all or decompose at elevated temperatures. - Markus -
Hi Markus,
First of all thank you so much for somehow clarification. And yes VFAs mean volatile fatty acids. Can you refer some articles describing sample preparation and other measures? I worked and analysis-ed samples through LC and the samples we ran were in liquid form and withstood at good range of temperatures.
Thank,
Asim
Hi Asim,
An overview of esterification can be found in the Handbook of Derivatives for Chromatography' (Second Edition, Karl Blau and John M. Halket).
I would like to mention briefly here two procedures that work quite good: 1. methyl ester with tetramethylammonium hydroxide, 2. methyl ester with trimethylanilinium hydroxide. Derivatization takes place quantitatively in the injector. - Markus -
P.S.: A second very good reference can be found here: https://www.researchgate.net/post/GC-MS_why_is_extraction_and_derivatisation_usually_done_in_two_steps?_ec=topicPostOverviewFollowedQuestions
At the levels you will find in disgestors you don't need to derivatize. You can directly inject a filtered sample using a polar capillary column (Wax, etc). Keep your injection volume relatively low (1-2 uL) and your injector nice and clean with a good inert liner.
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