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mobile phase problems

Posted: Wed Jun 07, 2006 8:29 am
by Magda
Hi! I'm running an application with a mobile phase consisting of 95% of the following buffer: pyrophosphate sodium decahydrate 10mM, Na2EDTA 10mM, Triethylamine 0.1% and 5% ACN. The column is an ODS C18. The problem is that the maximum column life is 1 week. What do you advice me to do? The problem here is that with this mobile phase I have the best chromatography for my analyte.
Thanks
Magda[/quote]

Posted: Wed Jun 07, 2006 11:04 am
by Koen Hollebekkers
Hello Magda,

It may be the best conditions for your separation, but the worst for your column!
Silica dissolves really easy at this pH.

There a few opinions, but the two most realistic are:
• In case you need separation efficiency, switch to hybrid type of columns (e.g. Gemini/XBridge)
• In case column efficiency is not important, switch to polymeric materials (e.g. PLRP-S).

If you want to stick to this aggressive mobile phase, you have to change the column !!