precipitation of phosphates in SEC-HPLC column

[anemostroke]

Hi all,
I just started in HPLC-SEC and I need your help.

I have run my analysis on an Agilent Bio SEC-3 column (mobile phase: 150mM phosphate buffer pH7), diconnected the column in order to check the detector and closed it provisory at both ends. it stayed like this for 2 days. precipitations were formed and I tried to redissolve the salts with the HPLC-grade water at a very low flow rate 0.005 ml/min. pressure was very high 2500-2700 psi (limit 3500 psi). I swifted to the mobile phase and after 20-30 min the pressure dropped at 10 psi and I could see the mobile phase exiting the column.

is this sudden drop of pressure normal?could the column be already destroyed? for the moment I have problems with the detector and I cannot check it.

thank you

[Gerhard Kratz]

You are not the first one who did this at the beginning.
Please flush the column in reversed flow, without connecting to the detector. Than rinse with the storage solvent recommended by the manufacturer.
Maybe you are a lucky starter and the column is still ok, not 100% but ok!
Otherwise don't wast more time and order a new column!
Good luck

[anemostroke]

thank you for your answer.