TFA vs. Formic Acid

[Yuhuan Tang]

We sometime have unwanted blank peak when using formic acid in mobile phase, I was told that TFA is a better replacement for formic acid. Beside possible suppression of the MS signal do you have any other issues when using TFA?

Please share your experience.

Thanks,
yt

[usuchrom]

Will you use formic acid at 99% pure? I use this and I have no "ghost" peaks. About the TFA, I think that it do not harm the MS signal. The only thing against the TFA is that during chromatography could Trifluoroacetyl some products.

[alexdwsn12]

TFA:
-Trifluoroacetic acid (TFA) is the simplest stable[1] perfluorinated carboxylic acid chemical compound, with the formula CF3CO2H.
- The use of trifluoroacetic acid in API-Electrospray may lead to the formation of ion pair with analytes and the consequence is ion suppression.

Formic Acid :
- Formic acid have a good volatility and is capable of lowering pH at value 2-3: therefore it is good choice in API-ES for compounds with a protonable group.