Column Withered / Column Dried

When running HPLC overnight, you may come in the morning to find the mobile phase has run out. You may worry that the column has dried out, but this is usually not an issue.
When the mobile phase reservoir empties and air enters the pump head, the plunger cannot expel the air and just spins freely, causing the mobile phase to stop moving before the column.
This means that even if the mobile phase runs out, the column will not immediately dry out.
To remove air from the flow path, you can remove the column, directly connect the line, and purge it with the mobile phase to resolve the issue.

But, is it never possible for the column to dry out?

If a silica-based HPLC column doesn't have end-plugs, or if the plugs are not tightly secured, the column can dry out.
When the column dries, the packing material inside can shrink, changing its state and leading to a loss in column performance.

While it's generally advisable to replace the column, there may be instances where it can be revived using the following method:

Run acetonitrile through the column for about 10 minutes, then replace it with the mobile phase and conduct an analysis.

If the analysis results are satisfactory, you can infer that the column has been revived. However, if you observe peak tailing or broadning, it means the column has not been successfully revived. In this case, your only option is to replace it with a new column.

It is important to use end-plugs when storing the column.

WF29 / YAZAWA Itaru,