Column rehydration - what if the column runs dry

An HPLC column may dry out because of long-time storage if the plugs are not properly tightened or it may run dry if air inadvertently is pumped into the column during use. A dehydrated column can be rehydrated by the outlined procedure.

Procedure to rehydrate an HPLC column

1. Connect the column to your LC system in reverse flow direction.
2. Do not connect the column to the detector.
3. Pump a filtered mobile phase of 20% methanol in distilled, deionized water over the column at half of the recommended maximum flow rate. Please note that reversed-phase columns require 60% methanol.
4. Continue this procedure until you are confident that the column has been rehydrated. Rehydration can take several hours, depending on the column size.
5. Connect the column to your LC system in proper flow direction.
6. Equilibrate with your normal mobile phase.
7. Perform the recommended QC tests to ensure that the column is performing properly.