Chromatography Forum

Hi,

I need to do trace level of monoethylene glycol and diethylene glycol in ethanol sample. Any suggestion on derivatize agent that will only works on glycol but not ethanol?

Hi, I need to do trace level of monoethylene glycol and diethylene glycol in ethanol sample. Any suggestion on derivatize agent that will only works on glycol but not ethanol?

Unfortunately the ethanol will also derivatize, but should be lost in the excess solvent/derivatizing agent peaks. You'll need lower temperatures to separate the derivatized ethylene glycol from those.

see viewtopic.php?f=3&t=22689

If you want to try the assay without derivatization, use a polar column, such as a "624" type. See the USP monograph for glycerin, has test for ethylene glycol and diethylene glycol at low levels, that should work; I've run that in glycerin samples, and it should be even simpler with just your sample matrix.

I need to meet a detection limit of 1 ppm for the glycols. I have try various type of columns for the direct sample injection. I have yet successful to meet the DL.