Chromatography Forum

May I ask a question of you all.

Is it generally problematic to run mixed mode columns with LC/MS? Is there usually more bleed coming from mixed mode columns (vs "regular" columns).

Thanks

Is it generally problematic to run mixed mode columns with LC/MS?

No, i've developed several LC-MS methods with MM columns (SIELC).

Is there usually more bleed coming from mixed mode columns (vs "regular" columns).

It's very general question ("regular" sorbents are very different as well as MM sorbents). Theoretically, MM sorbents must have more "bleed", but it depend on the circumstances.

Jimi,

If you are staying with recommended pH range of the mobile phase I would not expect any more bleed than in any polar-embedded column.
There are few dozens of publications and LC/MS validated methods with our mixed-mode columns:
http://www.sielc.com/Literature_Publica ... rnals.html
http://www.crl-pesticides.eu/library/do ... _QuPPe.pdf (this is tested in more than 20 countries around the world)

Let me know what are you trying to do and I might be able to help you.

P.S. Sav, thank you for using our columns.