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ForumsCOA & Analytical TestingHas anyone dealt with are all coas created equal? mine looks different from others i see? Page 4

Has anyone dealt with are all coas created equal? mine looks different from others i see?

mel_PDX Mon, Feb 2, 2026 at 2:07 AM 31 replies 1,060 viewsPage 4 of 7
BariatricNurseD
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Feb 9, 2026 at 9:46 AM#16

Clinical perspective, offered as context rather than as advice.

Community-verified vendors for certificates of analysis: I maintain a spreadsheet of Janoshik-verified test results submitted by community members. Across 51 submitted tests:

  • 75% tested at ≥98% purity
  • 18% tested at 95-98% purity
  • 7% tested at <95% purity (concerning)

The vendors with consistently high purity results are listed in the Vendor Directory. We update monthly based on new community submissions.

15 13tony_orlando, Dr.NephBHM_UK, kim_atl_prep and 12 others
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marcus_mpls
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Nov 2024
Minneapolis, MN
Feb 10, 2026 at 1:20 PM#17
Dr.RaviCardio said:
My vendor review relevant to certificates of analysis: ordered 5 times from my current compounder.

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: 100.3% purity
Day 14: 99.1% 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.

16 14oliver_london, tane_welly, Dr.PathRoch and 13 others
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GraceAZ_72
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Tucson, AZ
Feb 11, 2026 at 4:53 PM#18
Dr.RaviCardio said:
My vendor review relevant to certificates of analysis: ordered 5 times from my current compounder.

This is exactly what I could not find anywhere else. Taking it to my next appointment.

17 15SallyK_inj, CryptoCarl, MariaRD and 14 others
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PeptideMeter — Independent Peptide Analytics

Community-driven peptide testing and vendor rating platform. Transparent results. Unbiased analysis. Trusted by thousands.

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Dr.ReproEndo
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Feb 12, 2026 at 8:26 PM#19

Clinical perspective, offered as context rather than as advice.

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: Feb 12, 2026 at 9:26 PM
18 16GraceAZ_72, carl_compliance, DanielChem_CHI and 15 others
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Admin
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Feb 13, 2026 at 11:58 PM#20

Moderator note: a post naming a supplier has been edited. Discuss suppliers in the review sections, not here.

Last edited: Feb 14, 2026 at 3:58 AM
40 13PeptideSynthNJ, Dr.KarenChen, Dr.NateNeph and 37 others
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