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

Understanding peptide purity percentages — what worked for you?

Dr.NateNeph Tue, Nov 11, 2025 at 4:06 PM 29 replies 1,285 viewsPage 6 of 6
bri_stats
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Nov 20, 2025 at 6:51 PM#26

Adding the numbers, since they settle part of this. The boring version of this is the one that works, and the boring version is: measure a baseline, change one variable, wait, measure again under the same conditions. Nobody wants that answer and it is still the answer.

Last edited: Nov 20, 2025 at 10:51 PM
6 6sarah_nash92, FitDadDave, RunnerRach and 3 others
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jennifer_SEA
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Nov 21, 2025 at 1:06 PM#27

A narrower follow-up, since the general answer is now clear:

What would you measure differently if you were starting again?

5 5Dr.ReproEndo, lucas_SP_BR, lisa_labSD and 2 others
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Dr.KarenChen
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Nov 22, 2025 at 7:22 AM#28
bri_stats said:
The boring version of this is the one that works, and the boring version is: measure a baseline, change one variable, wait, measure again under the…

I do not accept the framing. The question has been narrowed to the version that has a tidy answer, and the part that was dropped is the part the OP actually asked about.

4 4TomFromTexas, mike.trainer_LA, sarah_nash92 and 1 other
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anna.melb_AU
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Nov 23, 2025 at 1:38 AM#29
bri_stats said:
The boring version of this is the one that works, and the boring version is: measure a baseline, change one variable, wait, measure again under the…

Correct as far as it goes. The part it does not cover is what to do when the honest answer is "not enough data", which is more often than anyone likes.

3 3tammy_FL, Dr.LipidDallas, alex_tucson
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Dr.NateNeph
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Nov 23, 2025 at 7:55 PM#30

Reporting back.

Late follow-up. I did not do what was suggested, I did something adjacent, and it worked; posting the difference in case it matters to somebody.

31 6RickReta_CO, PharmHunterJen, TomTeleRx and 28 others
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