during LC/MS runs we lately encountered contaminants with the following
m/z values: 371.8 Da and 445.4 Da. The 445.4 Da contaminant breaks into an
intense series of 342, 206, 147, and 72 Da fragments when subjected to
fragmentation. We see these background peaks when using either 0.02%
acetic acid/methanol, or 0.01% HFBA/0.1% acetic acid/acetonitrile as
solvent systems. Has anybody encountered the same background ions, and if
so what are they?
Many thanks for any input.
Best regards
Paul Jenoe
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Paul Jenoe, PhD
Department of Biochemistry
Biozentrum of the University of Basel
Klingelbergstrasse 70
CH-4056 Basel
Switzerland
Tel. ++41 61 267 21 68
Fax. ++41 61 267 21 48
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