Chromatography Forum

Can anybody suggest me a capillary GC method for the Analysis of TFA.It is present in a salt form in an intermediate .we only have FID detector

thx in advance

Did you want a headspace analysis or a direct injection analysis?

preferably Headspace GC method.

thx

VERY DIFFICULT to do as a free acid. As a salt, impossible(?), as most salts have very little volatility unless they disassociate into the free acid.

and you want to use FID, where TFA has a rather low relative FID response.

Perhaps a derivative might be the best direction to follow. I vaguely remember reading a method to do TFA by headspace but don't know the parameters.

Making a propyl or butyl ester and doing headspace on the reaction vial might be advisable.

I dread trying to get low ppm amounts of a salt through a headspace analyzer or using a manual syringe !

good luck sorry I cannot be of more help.

Rod

I have Anal.chem.publication here for the determination of TFA in the form of Methyl trifluoroacetate using HSGC .they used DMS(dimethyl sulfate) in Conc. sulfuric acid to derivatize TFA to MTFA then detecting it by ECD.I might try derivatizing it with MeOH/sulfuric acid then detect by GC/MS


Thanks anyway