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

Mass spectrometry for peptide identity verification — March 2026

TirzTom Fri, Jan 9, 2026 at 3:52 PM 40 replies 1,536 viewsPage 5 of 8
sarah_TO
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Jan 17, 2026 at 10:59 PM#21

From the other side of the consultation, briefly. The distinction that resolves most of these threads is between what is true on average and what is true for one person. Both are real; they answer different questions and get quoted as if they were the same one.

8 6andrew_nyc, Dr.EndoEP, GraceAZ_72 and 5 others
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sarah_nash92
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Nashville, TN
Jan 20, 2026 at 5:04 PM#22
sarah_TO said:
The distinction that resolves most of these threads is between what is true on average and what is true for one person.

Mine went the same way, slower. I had assumed I was the exception until I read this.

Last edited: Jan 20, 2026 at 11:04 PM
9 7JakeSmashed95, NauseaFreeNow, SteveThurs and 6 others
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RunnerRach
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Boston, MA
Jan 23, 2026 at 11:07 AM#23
sarah_TO said:
The distinction that resolves most of these threads is between what is true on average and what is true for one person.

Adding the part of the answer the thread has not reached. The version of this that has an answer is narrower than the version being asked. Narrow it and it becomes tractable; leave it broad and the thread will produce nine confident and incompatible replies.

Correct me if the detail matters more than I have assumed.

Last edited: Jan 23, 2026 at 2:07 PM
10 8Dr.RaviCardio, jennifer_SEA, tyler_CSCS and 7 others
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PeptideSynthNJ
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Princeton, NJ
Jan 26, 2026 at 5:09 AM#24

One concrete data point for the thread. If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way. Most of the apparent contradictions in these threads dissolve at that step.

11 9MikeKY_noInsulin, Dr.RaviCardio, jennifer_SEA and 8 others
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JessicaH_TX
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Houston, TX
Jan 28, 2026 at 11:09 PM#25

Following on from sarah_TO — and this may be the naive question:

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

12 10tony_orlando, Dr.NephBHM_UK, kim_atl_prep and 9 others
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