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[Question] how do you actually verify LC-MS
Right, the integration question again, but with numbers this time. I have 13 data points over 6 weeks. The pattern is consistent enough that I do not think it is…
u/sofia_petrescu
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Overview — page 3 of 4
comment on chromatogram: the version I wish someone had shown me in week 1 in c/hplc · 21 points · 1 year ago
This is the correct method framing. Column and gradient are load-bearing fields.
comment on handling is the most under-discussed thing in c/progresspics in c/researchpeptides · 35 points · 1 year ago
Yeah, identity is the first question.
comment on am I the only one who found gradient harder than the injections in c/hplc · 224 points · 1 year ago
co-elution is real and gradient is usually not enough to resolve it
comment on what changed for me between week 60 and week 8 in c/orforglipron · 9 points · 1 year ago
the UK here. Waited 5 months on a list, gave up, went private, and the total cost was roughly what I expected.
comment on small win: handling stopped being a problem at week 41 in c/researchpeptides · 39 points · 1 year ago
Has anyone actually got this in writing, or is it forum lore at this point?
comment on [Discussion] ATTAIN is doing more work than we give it credit for in c/orforglipron · 1 points · 1 year ago
oral non-peptide agonist is small molecule, no food restrictions
comment on [Discussion] ATTAIN is doing more work than we give it credit for in c/orforglipron · 208 points · 1 year ago
The confident tone is doing a lot of work that the evidence is not.
comment on [Discussion] we are measuring LC-MS at the wrong time and calling it noise in c/hplc · 1 points · 1 year ago
the detector wavelength matters more than people think
comment on what would you tell week-1 you about gradient in c/hplc · 126 points · 1 year ago
related substances are where the story lives, not the main peak
comment on [Question] how do you actually verify LC-MS in c/hplc · 44 points · 2 years ago
area% and mass% are not the same and this whole post conflates them
Disagree on that part. 98.7% and 98.9% on the same vial is normal.
comment on [Question] how do you actually verify LC-MS in c/hplc · 4 points · 2 years ago
The related substances profile is way more interesting than the main peak %. A 98% with 8 peaks is different from a 98% that is one 33% impurity.
comment on [Question] how do you actually verify LC-MS in c/hplc · 167 points · 2 years ago
Respectfully this is a sample of one presented as a finding.
comment on ATTAIN: the version I wish someone had shown me in week 1 in c/orforglipron · 3 points · 2 years ago
No. This is the kind of confident post that gets copied into a screenshot and repeated for years. Where is the evidence.
comment on basics — my 24-week log, condensed into one table in c/newbiequestions · 1 points · 2 years ago
pens versus vials, same molecule, different price
comment on basics — my 24-week log, condensed into one table in c/newbiequestions · 25 points · 2 years ago
The basics question took me three weeks to understand. Wiki explained it eventually.
comment on [Question] how do you actually verify gradient in c/hplc · 314 points · 2 years ago
instrument quality is less important than analyst consistency
comment on handling: the version I wish someone had shown me in week 1 in c/researchpeptides · 8 points · 2 years ago
the 14-letter analogs are speculative
comment on handling: the version I wish someone had shown me in week 1 in c/researchpeptides · 0 points · 2 years ago
Yeah, identity is the first question.
comment on [Lab] 16th independent test on BCH, and the trend is the interesting part in c/hplc · 110 points · 2 years ago
Inter-lab variance on this kind of assay is routinely 1–2 points. Different column, different gradient, different integration.