how would a truncation sequence show up
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#hplc-massspec 2025-11-21
Friday13 messages3 participantstimes are UTC
Highlights from this day
- gradient_greg — how would a truncation sequence show up 19:39
- gradient_greg — is a tailing factor of anything specific a problem 20:12
- underfill_uma — baseline drift on a gradient is normal. baseline drift on an isocratic hold is your column 20:20
- gradient_greg — plus sixteen, is that always oxidation 20:32
does ms/ms actually prove identity or just make it very likely
if somebody says they ran a mass spec and does not show you a spectrum, that is a claim, not a result
update from 13 months ago: switched to asking for the chromatogram rather than the number and it changed everything
is a tailing factor of anything specific a problem
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baseline drift on a gradient is normal. baseline drift on an isocratic hold is your column
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truncations show as a mass deficit matching one or more residues. you need the sequence to say which
plus sixteen, is that always oxidation
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integration choices move the number by a few tenths easily. that is most of your inter-lab variance, ill dig out the number
is uv at 214 or 280 better for peptides
thats the solvent peak
run a blank
if the number you are staring at is a third of what you expected, do the charge state arithmetic before you panic