Probleam with gchs analysis of acetic acid and triethylamine

Chromatography Forum: GC Archives: Probleam with gchs analysis of acetic acid and triethylamine
Top of pagePrevious messageNext messageBottom of pageLink to this message  By Anonymous on Thursday, January 24, 2002 - 07:11 am:

i am go na validate a gchs method for my bulk sample as a part of my DMF SO I HAVE TO SET THE METHOD FOR 8 SOLVENTS IN A SINGLE RUN AND I AM SUCCESSFUL FOR A GREAT EXTENT BY DOING THAT BUT PROBLEAM IS I AM NOT GETTING A LINEARITY AND RECOVERY AND PRECISON FOR THIS TWO SOLVENTS SO I AM GIVING A DETAL WHATS MY METHOD CAN YOU ASSIST WHAT CAN BE THE PROBLEAM


Top of pagePrevious messageNext messageBottom of pageLink to this message  By Rodney on Friday, January 25, 2002 - 06:55 am:

The problem may be you are forming a salt with the acetic acid. I have done TEA acetate in peptides with linearity with a LOD of 50ppm (measured as the free base). R2=0.9998

This was from DMSO/water not DMF.

Do the acetic acid separately by ion chromatography as the acetate.

A purge and trap GC-MS method for TEA gave 0 ppm for samples I later discovered contained several hundred ppm of TEA-acetate.

Good luck, it ain't easy.

Rodney George
Gas Separations Research
Supelco


Top of pagePrevious messageNext messageBottom of pageLink to this message  By Montse on Monday, February 18, 2002 - 05:45 am:

I have no experience with TEA, but I had the same problem with acetic acid. I solved it changing from an OVI-G43 column (6%cyanopropylphenil-dimetylpolysiloxane) to a DBWAX, which gives higher and more symmetric acetic acid peaks.


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