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ForumsCOA & Analytical TestingMass spectrometry for peptide identity verification — March 2026 Page 5

Mass spectrometry for peptide identity verification — March 2026

Dr.ObesityMed Thu, Apr 30, 2026 at 8:44 AM 29 replies 706 viewsPage 5 of 6
adam_van
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May 6, 2026 at 2:31 AM#21
PeptideSynthNJ said:
Practical: whatever you change, write down the date and the reason.

Careful with the causal language. Two things moving together in a period when five things changed is not a mechanism, and stating it as one makes the thread less useful to somebody reading it later.

4 2FranDenver, Dr.BariatricHTX, LindaRN_retired and 1 other
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COA_Karl
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May 7, 2026 at 7:49 PM#22
PeptideSynthNJ said:
Practical: whatever you change, write down the date and the reason.

That is right, and it stops being right at the edges. The general case is well behaved; the interesting cases in this thread are all at the boundary where the general case breaks.

5 3jim_asheville, matt_MKE, Dr.ReproEndo and 2 others
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tane_welly
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May 9, 2026 at 1:06 PM#23
PeptideSynthNJ said:
Practical: whatever you change, write down the date and the reason.

Genuinely useful, thank you. I had the facts and not the framework. I will report back once I have actually tried it.

Last edited: May 9, 2026 at 4:06 PM
6 4DanielChem_CHI, marco_milano, pam_columbus and 3 others
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Dr.ObesityLA
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May 11, 2026 at 6:22 AM#24

Adding the clinical framing, because it changes how the question reads. There is a difference between no evidence and evidence of no effect, and this subject is one where the two get swapped freely in both directions.

7 5chris_chi24, tampaLisa73, KarenAZ_mom and 4 others
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pam_stl
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May 12, 2026 at 11:37 PM#25
Dr.ObesityLA said:
There is a difference between no evidence and evidence of no effect, and this subject is one where the two get swapped freely in both directions.

This is my experience too, for whatever a second data point is worth. Posting only so the count is not one.

8 6RegAffairsDC, BiostatsBrad, PeptideSynthNJ and 5 others
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