Retention times longer than expected for target analytes
All ICs for al applications
- Check that the flow rate is what is expected.
- If eluent is prepared manually, double-check preparation or reagents used for preparation, including water.
- If system has RFIC-EG, have servicer go through steps to verify whether EG module/electronics are working properly, which should determine whether the EGC must be replaced.
- Review whether a new column has been installed recently and the age of the outgoing column (chromatography may have become less accurate over time).
- Make sure the same column types are being used for direct comparison.
Generally, either the flow rate or the eluent strength has diminished. In some cases, a new column will appear to push retention of analytes later, when, in reality, an older column has likely lost the capacity to do so.