My column packing dried out

[daidragon12]

Hello all,

I'm very new with HPLC. Last time I forgot to cap my HPLC column and I believe it caused the packing to dry out. I tried to search over the net and this forum if there is any way I could rehydrate my column, and currently I'm installing the column backward and flush them with 20% methanol. Is that true? Or is it already ruined? (hope not or gonna get kill by my supervisor)

My column is Agilent Eclispe XDB-C18 4.6mm x 250mm.

Thank you for the help!

[scottythree]

How long did it go uncapped? Mine was still fine after I accidentally got lost (under an LC) for over a month.

[Shilpag]

If your mobile phase had any buffer in it ,there would have been evaporation of water and recrystallization of buffer salts.If this is the case the column may have been damaged.But if your mobile phase was purely solvent and water you can regenerate the column by passing degassed mobile phase through it.

[HPLCaddict]

The only way to know if it has been damaged is to try.
Rehydrate the column, preferably at a low flow at the beginning and gradually increase the flow. Eluent is freely flowling without much more backpressure than before? Then at least no big deposits of precipitated buffer inside It might be advantageous to finally use a high flow rate and thus create a big backpressure in order to get the last few bubbles out.
Everything looks fine? Equillibrate with a suitable mobile phase and rerun some analysis you've done before. Are the results comparable? Congratulations! Do they look terribly different? Go and confess to your supervisor .
I've had several columns used for normal phase operations that had been stored with solvents like hexane or octane. Not very good with cartridge columns since they're never really tightly closed. They seemed completely dried out but could be revived without problems .

[daidragon12]

Thanks!

Luckily last time I did wash the column quite long. I always kept my column with the 50% methanol, so I think I don't have much buffer left in the column to precipitate. Yesterday I tried to rehydrate for half a day, using 20% methanol and increase it to 60% later. And luckily it worked! Tried to run the standard and it looks fine.

To Scotty, I left it uncapped for two weeks, just before winter break. I guess temperature somehow would slow down the crsytalization. I'm so relieved that I don't have to confess about this!