Preparation of mobile phase for Ion-pair RP-HPLC

[javier.pec]

Hi

I am working with ion pair RP HPLC. The composition of mobile phase is 0.005 M sodium 1-heptanesulfonate dissolved in water and mixing with acetonitrile.

When I am doing the degassing step of mobile phase using a kitasato and vaccum pump, the results is a lot of foam formation inside of kitasato.

Can you give some recommendations to prevent foam formation?

Thank you

JP

[JI2002]

sodium 1-heptanesulfonate is a surfactant. It's not surprising for you to see foam during degassing by vacuum. Try degassing by sonication.

[hossam kamal]

hi javier,
of course heptanesulfonate causes foam ,as JI2002 says difenitely sonication will fix that problem

[lmh]

If you choose to go for sonication, do remember that sonication without a vacuum usually has little, if any effect on dissolved gases.

[Markus Laeubli, Metrohm]

Degassing water and organic solvent first might be a solution.