within inter-lab range
#hplc-massspec 2026-06-03
Wednesday13 messages4 participantstimes are UTC
Highlights from this day
- monoisotopic — why does integration change the number so much i was wrong about tailing factor. it is usually the injection or the pH, not the column 17:55
- void_volume — plus sixteen, is that always oxidation 18:09
- zoya_zeros — a dimer usually shows up late and at roughly double the mass. the chromatogram alone will not tell you 18:21
why does integration change the number so much
i was wrong about tailing factor. it is usually the injection or the pH, not the column
deamidation is about plus 0.98 Da. it is not a rounding error, it is a degradant
[edited]baseline is drifting badly, is that the column or the mobile phase
right so tirzepatide is about 4813.5 Da, so 2+ is near 2407.8 and 3+ near 1605.5
plus sixteen, is that always oxidation
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monoisotopic and average diverge more the bigger the molecule. say which one you are quoting
ms/ms or it isnt identity
if the lab reports area percent without stating the wavelength, the number is less useful than it looks
the first peak is the solvent. it is always the solvent
retention time is a hint
ask for the trace
a dimer usually shows up late and at roughly double the mass. the chromatogram alone will not tell you
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