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Evidence-based GLP-1 & peptide discussion since 2023
ForumsCOA & Analytical TestingCommunity-funded testing initiative — pooled resources for independent COAs Page 4

Community-funded testing initiative — pooled resources for independent COAs

VendorMark Thu, Jun 4, 2026 at 10:01 AM 19 replies 532 viewsPage 4 of 4
Dr.BariatricHTX
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Jun 6, 2026 at 11:09 PM#16

Adding the clinical framing, because it changes how the question reads.

Reconstituted peptide stability data for certificates of analysis: I had Janoshik test my reconstituted vial at day 1, day 14, and day 28 stored in the refrigerator.

Day 1: 100.5% purity
Day 14: 99.2% purity
Day 28: 97.3% purity

Minimal degradation over 28 days when properly refrigerated. This confirms the standard 28-day beyond-use date is appropriate. Beyond 28 days, I'd reconstitute a fresh vial to be safe.

Last edited: Jun 7, 2026 at 5:09 AM
44 17CarlaRPh_TPA, steph_laguna, fiona_glasgow and 41 others
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Dr.PathRoch
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Jun 7, 2026 at 9:10 AM#17
hank_denver said:
HPLC results interpretation for certificates of analysis: when you get your Janoshik report back, here's what the numbers mean: Purity %: Should be…

COA red flags for certificates of analysis — here's what to look for when reviewing a Certificate of Analysis:

  • No HPLC data: If there's no chromatography graph, it's not a real COA
  • Exact 100% purity: Suspicious — real testing always shows slight variation
  • No batch number: Can't trace back to specific production
  • No endotoxin testing: For injectables, this is essential
  • Template looks like it was made in Word: Professional labs have standardized formats

I have seen fake COAs that are literally photoshopped. Always verify independently if possible.

Last edited: Jun 7, 2026 at 3:10 PM
45 18InsuranceTom, WendyG_ATL, SaraMom3 and 42 others
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wei_SG
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Jun 7, 2026 at 7:11 PM#18

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

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

Last edited: Jun 7, 2026 at 8:11 PM
46 19Dr.MetabolicMD, RetaRick_CA, JenPlateau and 43 others
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Sigma-Aldrich — Research-Grade Standards

Certified reference materials, analytical reagents, and research-grade standards for peptide verification. Trusted by laboratories worldwide.

Shop Reference Standards
ricardo_MIA
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Jun 8, 2026 at 5:12 AM#19
Dr.PathRoch said:
COA red flags for certificates of analysis — here's what to look for when reviewing a Certificate of Analysis: No HPLC data: If there's no…

Mass spectrometry confirmation for certificates of analysis: beyond HPLC purity, mass spec tells you the molecule's exact molecular weight. This confirms identity — not just purity.

Why this matters: HPLC can show you a "pure" compound, but if it's pure of the WRONG compound, purity is meaningless. Mass spec at m/z 4113.58 Da confirms it's actually semaglutide. My Janoshik report includes both HPLC and mass spec.

If your testing provider only offers HPLC, consider upgrading to include mass spec for at least your first batch from a new vendor.

Last edited: Jun 8, 2026 at 10:12 AM
47 20KetoKyle, CanadaChris, ZaraB_AL and 44 others
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mike_mod
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Jun 8, 2026 at 3:12 PM#20

Moderator note: two posts asking for a source have been merged into one. Please search the thread before asking again.

Last edited: Jun 8, 2026 at 5:12 PM
19 17PurityPaulOR, MaxMetOK, MounjBrad and 16 others
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