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- Posts: 2
- Joined: Mon Oct 30, 2017 5:33 pm
My GC-MS system (Trace Ultra and ISQ) is contaminated with diisopropylnapthalene (DIPN) isomers and I can't figure out where it is coming from. It is present even in blank injections. I have swapped columns (30m DB-5 to 60m DB-5MS+DG), syringes, septa, solvents, wash bottles, inlet liners, etc. and cleaned the inlet thoroughly. I replaced the cartridge in the gas filter. Ours is a geochemistry lab so DIPN is not something we analyze . . . at least not deliberately. The concentration has increased over the past year until it is now a prominent set of peaks in an otherwise clean n-hexane injection.
There is a thread from a few years ago on this forum about DIPN contamination, but no resolution. Any suggestions would be very much appreciated.
Thanks,
Michael