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installing your column - 2006/06/12 18:33
When installing your column into an FID jet, never pass the column through the flame. This will burn the inner (phase) and outer (polyimide) coatings and will cause higher background signals.
Purge column with oxygen-free carrier gas for at least 30 minutes before heating GC oven.
When storing a capillary column, seal the column ends with a used septum. Remember to cut at least 3cm from each column end before re-installation.
If you're having problems with solvent focusing, or early eluting peaks seem broad or lop-sided in splitless injection, then try using a column with a thicker film.
Set the FID temperature 20°C above the maximum method temperature, 250°C is usually the recommended temperature.
When peak shape deteriorates, replace the liner immediately and cut 30cm from the front end of the column.
When changing your column, liner or septum, SGE recommends lowering the injector temperature to <100°C to prevent stripping the liner deactivation. This is especially important for the analysis of trace levels of active compounds.
Always re-tighten Graphite / Vespel® ferrules by ¼ to ½ turn after the first 2-3 oven cycles.
To prevent increasing retention times in your chromatography, replace the septum daily.
Condition column at:
a. 20°C above the method temperature or
b. the recommended maximum column temperature (whichever temperature is lower).
If the injection port temperature is not specified in the method, 250°C is usually the recommended temperature.
Always use SilTite™ or Graphite/Vespel® ferrules when connecting a column to a GC/MS interface.
For maximum FID sensitivity, set the air flow 10 times higher than the hydrogen flow.
To extend the lifetime of your packed column, ensure the oven temperature is 50°C, or less, before turning off the carrier gas.
Do not use plastic tubing in GC systems. Plastic tubing, when used for general plumbing, can absorb up to 20% moisture allowing external laboratory gases to transpire through the tubing. SGE recommends stainless steel tubing to be used throughout the GC system.
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