After installing a (new) column the sensitivity is lost
Immediately after installation of a (new) column a relatively high cell current is observed, the baseline drifts continuously and is noisy.
Installation of a new or used column
The problems started with exchanging the column.
A new column usually contains traces of contaminants from the production process. In UV methods this is not a problem but in ECD it contaminates the electrode and results in deterioration of performance. Prior to using a new column check the manufacturer’s instructions for compatible washing solutions. For reversed phase columns washing out with methanol/water (80/20) or similar for 24 hrs at a low flow rate is recommended. Disconnect the cell during this process. If a column is installed that was previously used for non-EC applications the same procedure is recommended since LC-EC conditions are usually quite different.
Read more in this KB paper…