Hello

The problem of Hexansulfonic acid Sodium salt is its high price. I'm looking for a method for Dequalinium chloride and its related substances on a reversed phase column. In the EP, the mentioned salt is used. Does anybody know another method without the use of Hexansulfonic acid Sodium salt ?

Thank you for every hint

Dear Florian;

If your method employs HSA as ion-pair reagent it is probably there to give retention of the analyte in the column. This means that you can not eliminate the ion-pair reagent completely if you want to maintain the same column. The high cost of HSA and similar reagents comes from the fact that they are purified to meet UV transparency requirements. If your method specifies higher wavelengths, such as, 250 nm or higher, then probably you can use cheaper grandes of HSA.

In some instances, ion-pair methods can be replaced by ion-exhcnage ones. This will require a totally different column and most likely you will need to add some salt to the mobile phase, but this salt is likely to be cheaper.

I hope this helps you. Good luck.

Benjamin

I might suggest that the cost of the ion-pair reagent is not that large when the total cost of labor, overhead, instrument cost, and other supplies are taken into consideration. Minimizing labor costs brings most bang for the buck. And think of the cost of developing or validating new test methodology.

Heptafluorobutyric will also work in the place of sodium hexanesulfonate (although some minor method adjustments may be necessary) athough generally similar purity material has a similar pricetag. But really, although both reagents are much more expensive on a per gram basis than acetonitrile or methanol, typically the contribution of the cost per liter is greater for the solvent than the ion pair reagent, as much more solvent is used per liter.