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Evidence-based GLP-1 & peptide discussion since 2023
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
TrialNerd_Beth
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May 6, 2026 at 2:31 AM#21

Clinical perspective, offered as context rather than as advice. The useful move here is to separate what is established from what is widely repeated. Those two sets overlap less than the confident tone of most write-ups suggests, and the second set is where nearly all the disagreement on this board comes from.

4 2RickReta_CO, PharmHunterJen, TomTeleRx and 1 other
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tampaLisa73
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May 7, 2026 at 7:49 PM#22
TrialNerd_Beth said:
The useful move here is to separate what is established from what is widely repeated.

This matches mine closely enough to be worth saying so out loud. The detail I would add is minor and it is already implied above.

5 3FitDadDave, RunnerRach, TrialNerd_Beth and 2 others
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InsuranceTom
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May 9, 2026 at 1:06 PM#23
TrialNerd_Beth said:
The useful move here is to separate what is established from what is widely repeated.

Coming at TrialNerd_Beth’s question from a different direction. Whatever the answer turns out to be, the method for getting there is the same: state the assumption, do the arithmetic in public, and invite the correction. That is slower than asserting, and it is the only version that survives being wrong.

6 4Dr.ReproEndo, lucas_SP_BR, lisa_labSD and 3 others
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DoseLogDan
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Feb 2025
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May 11, 2026 at 6:22 AM#24

Adding the numbers, since they settle part of this. Say what you would expect to see if you were wrong, before you look. It is a small discipline and it changes what you notice.

Last edited: May 11, 2026 at 7:22 AM
7 5sophie_paris, mel_PDX, Dr.AddMedPHL and 4 others
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Dr.NateNeph
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May 12, 2026 at 11:37 PM#25

One thing that is still open after TrialNerd_Beth’s answer:

Did your prescriber agree with that reading, and if not what was their objection?

8 6RickReta_CO, PharmHunterJen, TomTeleRx and 5 others
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