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- Posts: 23
- Joined: Wed Feb 06, 2019 8:59 pm
I am analyzing chlorinated phenols with BSTFA derivatization using a GC-MS. The GC column is Agilent J&W DB-1701 and EI-MS. After tens of injections, I noticed that the signal intensities are dropping and one of the chlorinated phenols cannot be detected any more.
When I switch to another same type GC-MS, I could see all of them again. This suggests that the chlorinated phenols are contaminating somewhere in the GC-MS system. But I have no idea where. Any suggestions about the contamination and precaution for this contamination are appreciated! Thanks.