Mass Spec compatible electrolyte

[CoCo]

Hi, Friends,

I need help to find some Mass Spec friendly electrolyte, so the sample can be directly analyzed by Mass Spec after electrochemical reaction. We are trying to avoid carboxylic acid. And the electrolyte should be able to dissolve in 100% acetonitrile.

Thank you

[Uwe Neue]

Depends on what pH you want. Ammonia or ammoniumbicarbonate would do what you have requested.

[CoCo]

Thank you for your help.

I don't know the pH requirement yet. Do you think tetramethyl ammonium (bromide, chloride, nitrite), trimethyl ammonium, para-toluene sulfonate or litherm triflate would be both EC and Mass friendly?

Thanks

[Uwe Neue]

A methylsulfonate might work. Maybe XL knows.

[Kostas Petritis]

None of them will work including the methylsulfonate as they are all non-volatile. About the electrolyte volatility and approximate concentration you can use check one of my previous articles in LC GC Europe:

Volatility evaluation of mobile phase/electrolyte additives for mass spectrometry
K. Petritis, C. Elfakir, M. Dreux
LC-GC Europe 15 (2002) 98-102

[Uwe Neue]

Just to clarify what Kostas meant by "none": I am sure that he excluded ammonia and ammoniumbicarbonate. We have been using both for years without any headaches.

[Kostas Petritis]

I apologize, I just read the electrolytes of the two previous posts. Of course ammonia and ammonium carbonate are very volatile...

[CoCo]

Thank you. I'll get the article you recommened.