Poor Sensitivity Or Sudden Loss In Sensitivity; Poor High Mass Response - Thermo Scientific TSQ 9000 Hardware Manual

Poor sensitivity or sudden loss in sensitivity.

Table 29. Possible Remedies for Poor Sensitivity or Sudden Loss is Sensitivity
Tune the system.
Check the system for air leaks and address them.
Make sure the ion volume is properly positioned. See
maintenance on your ion source, remove the ion source, verify that it is assembled correctly, and reinsert it into the TSQ 9000.
Make sure the GC column does not extend into the ion source. Use the column measuring tool to ensure the column is the correct length.
Make sure the GC column did not break inside the ion source. If necessary, remove the pieces from the ion source.
Clean or replace the GC injection port liner to remove possible contamination, trim the injector end of the column, or replace the septum.
Make sure the source magnets are positioned so that their south poles are facing up. Reposition them, if necessary.
Clean the ion source and lenses. See
Check the electron multiplier gain and make sure it is not too low. Retune the detector gain. Replace the electron multiplier, if necessary.
See Replacing the Electron Multiplier

Poor high mass response.

Table 30. Possible Remedies for Poor High Mass Response
Run a resolution tune to make sure the resolution is set correctly.
Clean the ion volume and lenses. See
Reduce the ion source temperature to reduce the amount of thermal decomposition and fragmentation of your analyte.
Check the system for air leaks and address them. See
Thermo Scientific
Reinserting the Ion Source Cartridge
Cleaning Durable Components
for details.
Cleaning Durable Components
Investigating Vacuum Issues
for details. If you recently performed
for details.
for details.
for details.
2
Troubleshooting
Investigating Sensitivity Issues
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