do the arithmetic
#hplc-massspec 2026-04-25
Saturday16 messages4 participantstimes are UTC
Highlights from this day
- LC_MS_Lena — monoisotopic and average diverge more the bigger the molecule. say which one you are quoting a dimer usually shows up late and at roughly double the mass. the… 21:43
- freeze_thaw — while im here two labs a point or two apart on the same lot is normal and gets mistaken for one of them being wrong constantly 21:45
- freeze_thaw — plus sixteen, is that always oxidation 21:57
- VialBot — Batch lookup G-0641: 4 independent reports on file, earliest 2026-02-27. 22:48
- hk_hplc — a warm transit can put a visible degradant peak on a chromatogram. that is what 23 days at ambient does, take that with a pinch of salt 22:55
ms/ms or it isnt identity
integration choices move the number by a few tenths easily. that is most of your inter-lab variance
thats a charge state
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a certificate with a number and no chromatogram is asking you to trust the integration you cannot see
monoisotopic and average diverge more the bigger the molecule. say which one you are quoting
a dimer usually shows up late and at roughly double the mass. the chromatogram alone will not tell you
shallow gradient
while im here two labs a point or two apart on the same lot is normal and gets mistaken for one of them being wrong constantly
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plus sixteen, is that always oxidation
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plus 16 is oxidation
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is there any point running a blank if the sample is the question
ms/ms sequencing is the only thing i would call identity. everything else is circumstantial
show me the spectrum
vial-kp-0925-front.png
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shallow gradients hide related substances behind the main peak. a steeper one separates and looks worse, honestly
Batch lookup G-0641: 4 independent reports on file, earliest 2026-02-27.
a warm transit can put a visible degradant peak on a chromatogram. that is what 23 days at ambient does, take that with a pinch of salt