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ForumsCOA & Analytical TestingBatch-to-batch purity variation — acceptable ranges Page 3

Batch-to-batch purity variation — acceptable ranges

kate.chem Wed, Mar 11, 2026 at 4:15 AM 15 replies 505 viewsPage 3 of 3
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Mar 11, 2026 at 8:30 AM#11

Moderator note: Reminder: nothing posted here constitutes medical advice. Consult your healthcare provider.

Tagging this for the weekly digest. 👍

37 4PedsEndoPhilly, SleepDoc_PDX, RegAffairsDC and 34 others
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RetaRick_CA
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Mar 11, 2026 at 8:47 AM#12

Slightly tangential to Batch-to-batch purity but BenResearch_OR reminded me — does anyone have experience combining this with metformin?

I know it is not exactly on-topic but it seems related enough to ask here rather than starting a new thread. Apologies if this has been covered — I did search first.

41 11AmyNC_wife, SkepticalSean, Dr.CardioMD and 38 others
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NeuroNate
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Mar 11, 2026 at 9:04 AM#13
SteveThurs said:
Follow-up question: how long did you wait before increasing your dose

This is exactly right. SteveThurs articulated what I have been trying to explain to my doctor for months. The Batch-to-batch purity aspect is the most important factor.

Last edited: Mar 11, 2026 at 3:04 PM
29 10sarah_TO, wendy_avl, jason_paloalto and 26 others
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Janoshik Analytical — Independent Testing

Trusted third-party HPLC & mass spectrometry analysis. Verify peptide purity with the lab the community relies on. Independent. Accurate. Transparent.

Verify Your Peptides
RickReta_CO
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Mar 11, 2026 at 9:21 AM#14

Saving this for reference. Top-tier content.

Last edited: Mar 11, 2026 at 2:21 PM
17 2tommy_boulder, hyun_seoul, jim_asheville and 14 others
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HPLC_Greg
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Mar 11, 2026 at 9:38 AM#15

Adding my data to this Batch-to-batch purity discussion:

MetricBaselineMonth 3Month 8
Weight246 lbs241 lbs201 lbs
A1C7.0%5.8%5.4%
hsCRP5.02.01.2

Protocol: Semaglutide 2.4mg/wk, resistance training 3x/wk, protein 1.3g/kg/day.

Last edited: Mar 11, 2026 at 3:38 PM
49 19SaraMom3, Dr.MetabolicMD, RetaRick_CA and 46 others
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