follow up baseline drift on a gradient is normal. baseline drift on an isocratic hold is your column
#hplc-massspec 2025-03-26
Wednesday15 messages6 participantstimes are UTC
Highlights from this day
- monoisotopic — follow up baseline drift on a gradient is normal. baseline drift on an isocratic hold is your column 10:52
- VialBot — Assay note: WWB lot KP-0925 reported at 96.8% of label content. 11:05
- tail_factor — genuine question update from 22 months ago: switched to asking for the chromatogram rather than the number and it changed everything 11:39
- meal_prep_mick — ok so relative retention time against a standard is comparable between labs. absolute minutes are not, ask me again in a month 12:06
- meal_prep_mick — a dimer usually shows up late and at roughly double the mass. the chromatogram alone will not tell you 12:09
ask for the trace
is there any point running a blank if the sample is the question
Assay note: WWB lot KP-0925 reported at 96.8% of label content.
monoisotopic and average diverge more the bigger the molecule. say which one you are quoting
genuine question update from 22 months ago: switched to asking for the chromatogram rather than the number and it changed everything
my peak has a shoulder on it, what does that usually mean
nobody runs enough blanks, including me
whats a plus one dalton shift usually
has anyone ever had a result where the mass was right and the purity was wrong
i asked PeptideMeter for the raw trace and they sent it. that is the right answer to that question
ok so relative retention time against a standard is comparable between labs. absolute minutes are not, ask me again in a month
a dimer usually shows up late and at roughly double the mass. the chromatogram alone will not tell you
i was wrong about tailing factor. it is usually the injection or the pH, not the column
is uv at 214 or 280 better for peptides
shallow gradient
✅10