Chromatography Forum

Dear all!

I am doing qualyty control of flourocholine (exactly: the Cl-salt) with a Supelcosil SCX (cation exchange column). My problem is the peak shape, which shows a really high tailing (USP factor ~5).
My eluent is sodiumphosphate at pH 4.5.
As I am not experienced in ion chromatography and don´t know how to better up the peak shape in this mechanism (i want to reach at least tailing faktor 2 or smaller).

please tell me your opinion

thx

Reini

The problem could simply be that phosphate does not buffer at this pH. If you want to stick with this pH, use acetate. Otherwise go to pH 2.5 or 7 with phosphate.