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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
SurmountFan_IN
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Nov 20, 2025 at 6:51 PM#26

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

How long did you give it before you decided it was working?

Last edited: Nov 20, 2025 at 7:51 PM
6 6DebRD_ATL, KristenIndy, MarkLI_maint and 3 others
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NurseLeah_Nash
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Nov 21, 2025 at 1:06 PM#27
Dr.PulmRoch said:
HPLC results interpretation for certificates of analysis: when you get your Janoshik report back, here's what the numbers mean: Purity %: Should be…

Worth saying that the confident version of this is more useful to the person writing it than to the person reading it.

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

5 5BiostatsBrad, PeptideSynthNJ, Dr.KarenChen and 2 others
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adam_van
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Nov 22, 2025 at 7:22 AM#28
Dr.PulmRoch said:
HPLC results interpretation for certificates of analysis: when you get your Janoshik report back, here's what the numbers mean: Purity %: Should be…

Correct, and worth adding that it is reversible. Nothing being described here is a one-way door, which changes how cautious it is reasonable to be.

4 4LindaRN_retired, tommy_boulder, hyun_seoul and 1 other
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paul_denver
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Nov 23, 2025 at 1:38 AM#29
Dr.PulmRoch said:
HPLC results interpretation for certificates of analysis: when you get your Janoshik report back, here's what the numbers mean: Purity %: Should be…

This answered a question I did not know how to ask.

3 3sarah_TO, wendy_avl, jason_paloalto
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Dr.NateNeph
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Nov 23, 2025 at 7:55 PM#30

OP back with an update, since a thread like this is useless without one.

Reporting back for the archive rather than for the thread: I did the narrow version of what was suggested, gave it the full interval, and it settled. Posting it because threads without a follow-up are half a thread.

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