How to test for basic sensitivity on the AutoSpec - WKB95113

OBJECTIVE or GOAL

To test the basic sensitivity of the AutoSpec to help aid diagnosis of GCMS dioxin sensitivity problems.

ENVIRONMENT

• AutoSpec Premier
• AutoSpec Ultima

PROCEDURE

1. Open all slits.
2. Use the following instrument conditions (typical dioxin source tune values):
   • Electron Energy = 33 to 35eV
   • Trap current = 650uA
   • Detector voltage = 180V
3. Empty reference tank, and then inject 2.0 ul of PFK and optimize ion intensity (leave syringe in place).
4. Ensure that m/z 69Da is >10V signal intensity. Sometimes the barrel of the PFK syringe can be removed from the septum tank to allow air to normalize flow.
5. Tune instrument to 10,000 resolution to @5% transmission (see WKB95120 for definition and WKB95218 on tuning to 10,000 resolution).
6. Sensitivity problem is due to the GC/autosampler/standard/sample.

ADDITIONAL INFORMATION

1. If >10V signal is not obtainable on m/z 69, confirm <1000 resolution by closing the collector slit (see WKB94413). If resolution is >1000, source or alpha slit is not correctly set. Contact Waters Service Support.

2. Confirm that the detector gain is within acceptable ranges (see WKB11558) Contact Waters Service Support.