Chromatography Forum

Hello!

I received a Partisil PAC column with MeOH/Water 85/15 as shipping solvent. I would like to convert to normal conditions. Does anyone know which solvent may I use?

To convert to normal phase conditions you will need to wash down both the column and your system with a solvent miscible in both your polar solvents and your non-polar solvents. In all likelihood that solvent is probably isopropyl alcohol (IPA). You must extensively wash all units of your LC with IPA making sure to remove your polar MP with IPA in all areas including your sample loops, autosampler, all major HPLC components and anything that could theoretically be introduced into the system. This also includes the column, which you may want to wash down for quite a few volumes, then remove, and continue washing out your system. After the IPA wash (depending on your solvent's miscibility), you may introduce your non-polar solvent and convert everything to normal phase. I'm not familiar with your column, but solvent wise this should do the trick. I'd recommend washing for at least 10-20 volumes of your system and 8-10 column volumes for your column. I'd also include a few blank injections with IPA in order to clean out any of your sample loops, including your autosampler.
You can probably find a more precise protocol by just looking it up or, if your column distributor has a catalogue, there should be a protocol within there.

Hope this helps,
TS

Not sure if this applies to you, but I was told that if you are converting from a RP method to a normal phase one on your system you should look into changing things like seals to ensure solvent compatibility.
The instrument manufacturer telephone technical support may be able to help with specifics here.
Kevin