2
Troubleshooting
Investigating Contamination Issues
126
ISQ 7000 Hardware Manual
Thermo Scientific
Chemical noise is at
m/z
207, 429, 355, 281.
Chemical noise is at
m/z
149, 167, 279.
Chemical noise is at
m/z
43, 57, 71, 85, 99, etc.
Spectra is showing solvent contamination.
Possible Remedies
Condition the column. It is best to condition the column outside of the ISQ 7000 instrument so the contaminants can escape into the air
instead of into the instrument.
Make sure the column has not been damaged as a result of exposure to oxygen. Find the source of the oxygen in the carrier gas or air leak,
and then recondition or replace the column.
Check the column and see if it has broken off in the ion volume. If necessary, remove the broken pieces.
If the baseline contains these masses, the septum is worn out or damaged and you should replace it. You should also check the injection
port liner for pieces of septa and replace the liner if necessary.
If chromatographic peaks contain these masses, check the vial septa or use solvent to wash the vials.
Possible Remedy
If these masses are visible in your data, it is likely that phthalates have contaminated your system. Isolate the source of the phthalates,
such as vial lids or plastic solvent containers, and either clean them or replace them.
Possible Remedies
If these masses are visible in your data, it is likely that your carrier gas tubing is contaminated. Isolate the source of hydrocarbon
contamination and remove it. Replace the carrier gas tubing or filters, if necessary.
Heat the ion source to at least 25 °C above your normal operating temperature and heat the transfer line to the maximum temperature
allowed by your column. Hold this temperature for 4-6 hours, then cool the system back to your normal temperature. If necessary, repeat
this process.
Possible Remedies
You may have components that are contaminated by cleaning solvents. Remove any recently cleaned component, bake it in the GC oven,
let them cool, and then blow them dry with a clean, oil-free gas stream.