When you say persistent alkane peaks, do you mean that they are part of the MS background (observed all the time) or that they appear in your chromatogram as peaks of ascending mass that elute one after another? The first case implies some leak of hydrocarbons into your MS system (e.g. offgassing etc) while the latter implies they are getting into your inlet with the injection and eluting through the GC system.
When you say persistent alkane peaks, do you mean that they are part of the MS background (observed all the time) or that they appear in your chromatogram as peaks of ascending mass that elute one after another? The first case implies some leak of hydrocarbons into your MS system (e.g. offgassing etc) while the latter implies they are getting into your inlet with the injection and eluting through the GC system.More
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Maybe column bleeding if you have an alcane terminated column.
If it’s a peak. It’s probably somewhere in the inlet or sample vial. If it’s continuous it sounds the MS contamination.More
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not the same, but the lab I'm working at has a gc system stuck to a high vacuum chamber for astrochemical research. It also does the same thing and we suspect it has to do with either the oil in the pumps being sucked back or the o-rings sublimating in high vacuum. It might be something that you have to put up with
not the same, but the lab I'm working at has a gc system stuck to a high vacuum chamber for astrochemical research. It also does the same thing and we suspect it has to do with either the oil in the pumps being sucked back or the o-rings sublimating in high vacuum. It might be something that you have to put up withMore
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