Chromatography Forum

There have been several posts on the use of TFA in LC-MS on this forum. If your MS must be used for several versatile applications and by different users, avoid TFA unless you don't mind having a few enemies in your lab. TFA persistence in the MS is very long even if you clean it thouroughly and ion suppression in negative ionization is almost total.

The firts link is about thiamine, not thiamine pyrophosphate.

TPP is there (see table 2 and chroms).

I think the first peak comes to early so i like to avoid this if posible.

It's not an issue if you will can validate method. I've successfully developed 3 methods even without column (FIA-MS; Flow Injection Analysis).

The second link is the aplication vlad from sielc developed for me. I ame trying to reproduce this but get horible results with b1 on my agilent 1290.

I think that your LC system contain some adsorption sites which cause TPP peak broadening (hypothesis).

There have been several posts on the use of TFA in LC-MS on this forum.

Some people just use TFA as FA (etc.) and make mistakes (configuration of LC system, wash solution, wash sequence, methods dev sequence etc.). We used several methods at single LC-MS (+-ESI) without issues within 3 years (two methods contained 0.05 - 0.025 %v TFA).

I agree that it's much more safely to avoid TFA when system already contain several validated methods and operators.

For avoiding TFA, in some applications where 0.1% formic acid isn't quite enough to improve peak-shape, you can use more formic acid without disaster. I have a regular method that uses 1%, and I've tried it to 2% before I got too scared and went back down again. I have a colleague who went up to 10% but I vaguely remember he dissolved part of his HPLC...