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- Posts: 50
- Joined: Mon Sep 28, 2015 11:47 pm
I have been having some problems with contamination in solvents. At our lab our solvents appear to become contaminated with similar substances over time. I am seeing some of ions 83, 281, 73, 267, 355, and 341. From my research these seem like typical column or septum bleed indicator ions, however, I have eliminated the column and septum as the cause of contamination. This leaves only the solvent. I also see two large peaks at the tail end of chromatograms. These compounds are composed of ions 59, 44 and 72. Again I do not know what these compounds are or where they are coming from. From their mass spectra they seem to be some kind of amide or slip agent. Here is an example data file for those interested: https://www.dropbox.com/s/zggheftcg4aiq ... 9.qgd?dl=0
Can anyone suggest where the contamination might be from? We use MS certified vials and septa. Our solvent is DCM. The solvent is dispensed via aspiration using transfer pipettes into the vials. The solvent is stored in a glass Schott bottle with plastic cap away from sunlight.
Any suggestions as to what might be causing the contamination, or how to reduce it? Thanks in advance!