Chromatography Forum

Hi,
I was just wondering if anyone had any decent references on evaluating solvent impurities used in sample prep
(Want to test DCM, Hexane and Isooctane). Our sample prep procedure requires concentrating a significant volume of solvent (~20 mL to 0.2 mL).
To test currently, I concentrate 40 mL to 0.2 mL to confirm that there are no peaks at the RT of our analytes. Is there a more rigorous technique or is this about it
Thanks

It is common practice to start with an empty tube and process the contents thorugh all the sample preparation steps and to perform the GC/MS analysis on the result. Some will call this a reagent blank, method blank or sample blank, depending on what steps are involved and who's definitions you are using. In some types of work I will prepare at least one blank of this nature in each batch of samples. This checks for contamination in solvents, reagents, etc as well as stuff that drifts into the room in the air.

Hi Don,
Thanks for the response. I will usually carry a method blank through our sample prep procedure just as QA/QC every few days. I was thinking more in general of what steps I can take to process the solvents as an independent check. And if there were anything I could reference for this (EPA method etc) I haven't had any luck finding anything as of yet.
Thanks