HPLC Troubleshooting - Changes in Sensitivity

If you notice loss or changes in sensitivity; common causes are described below.

Causes	Solutions
Injector issue	- Changes in dispensing volume of injector, use a system suitability sample to determine volume changes. - Check batch / method details to ensure the correct volume was programmed. - Increase needle and loop flushing protocols to ensure no carryover from injection. - Purging the injector metering pump.
Sample	- Degradation could reduce peak signal with increases in impurity peaks. Prepare a fresh sample. - Check sample preparation to ensure the appropriate concentration was prepared.
Detector	- If all peaks have changed in sensitivity check detector for issues and parameters. - Check the lifetime of the lamp and change if above the recommended limit. - Flow cell window(s) may need replacing.
Loss of column performance	- Check the peak widths and resolution. Test the performance of the column using your standard test for loss in performance.
Instrument leaks	- Check for loose fittings post injector on the system.