Chromatography Forum

Hi, every one!
I tried to use 10mM ammonium acetate in acetonitrile as mobile phase B for LCMSMS. However, the salt can't dissolve at all regardless adding aqus solution to ACN or the way round, or adding solid to ACN. However it is clearly many people in this forum have been using this reagent without problems. Please could anyone help me out of this issue?

Thanks a lot!

Salts or buffers are typically only added to the aqueous solvent, for exactly the reason you have discovered.

Salts or buffers are typically only added to the aqueous solvent, for exactly the reason you have discovered.

thanks very much! so actually salt concentration is decreasing when using gradient elution?

yes.