Chromatography Forum

Hi,

I'm pretty new to the forums and to liquid chromatography in general. I'm running a LCMS method on a C18 column and I was wondering if it is ok to wash and store columns in mobile phase containing acid, in this case 0.1% formic acid.

Thanks!

generally yes. just make sure that there is no salt on the column and that some amount of organic is in the mobile phase you use for storage. 10% acetonitrile with 0.1% FA will do the job.
success

I would not store the column in an acidic solution. The pH of 0.1% formic acid is about 2.7. This can cause slow hydrolysis of the bonded ligands (especially the end-capping) on prlonged storage. I would store the column in 100% acetonitrile. This is completely compatible with your mobile phase, so you can just run your method direct from the storage solvent.