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ForumsCOA & Analytical TestingUnderstanding peptide purity percentages — what worked for you? Page 6

Understanding peptide purity percentages — what worked for you?

LondonLisa Wed, Apr 16, 2025 at 10:14 AM 38 replies 2,088 viewsPage 6 of 8
BenResearch_OR
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May 9, 2025 at 3:54 PM#26
Dr.GutHealth said:
I tested my certificates of analysis batch through Janoshik — 98.4% purity.

Pushing back on Dr.GutHealth here. Pushing back on the anecdote-stacking. Twenty people reporting the same thing is twenty samples from the same self-selected pool, not twenty independent confirmations.

Last edited: May 9, 2025 at 4:54 PM
18 16julia.endo, JessicaM_2024, TomFromTexas and 15 others
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quinn_sf
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May 12, 2025 at 4:49 AM#27
Dr.GutHealth said:
I tested my certificates of analysis batch through Janoshik — 98.4% purity.

Agreed, and one caution: a single measurement is not a measurement. Anything that moves day to day needs a trend before it means anything at all.

19 17Dr.PathRoch, mona_PHX, andrew_nyc and 16 others
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JakeSmashed95
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May 14, 2025 at 5:43 PM#28
Dr.GutHealth said:
I tested my certificates of analysis batch through Janoshik — 98.4% purity.

Saving this. It is the first explanation that did not require me to already understand it. Adding it to my notes with a link back to this thread.

20 18alex_tucson, kevin_tulsa, Dr.PainCLE and 17 others
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Sigma-Aldrich — Research-Grade Standards

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anna.melb_AU
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May 17, 2025 at 6:35 AM#29

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.

21 19tammy_FL, Dr.LipidDallas, alex_tucson and 18 others
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LondonLisa
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May 19, 2025 at 7:26 PM#30

Closing the loop on my own question.

Following up because I said I would. I changed one thing, left everything else alone, and waited the full interval before looking. It resolved, and I cannot prove which half of that did it.

43 16SallyK_inj, CryptoCarl, MariaRD and 40 others
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