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ForumsCOA & Analytical TestingHas anyone dealt with are all coas created equal? mine looks different from others i see? Page 5

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 5 of 7
PharmacoVig_BOS
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Feb 15, 2026 at 3:17 AM#21
Dr.ReproEndo said:
Mass spectrometry confirmation for certificates of analysis: beyond HPLC purity, mass spec tells you the molecule's exact molecular weight.

Vendor quality matters when discussing certificates of analysis. I've tested my last 6 batches through Janoshik and purity has ranged from 98.9% to 100.7%. Consistency is key.

For anyone new: always request the COA, and consider independent verification. The $300 for a Janoshik test is worth the peace of mind.

41 14amsterdam_pete, LondonLisa, mike_nyc and 38 others
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kate.chem
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Feb 19, 2026 at 8:23 PM#22

Adding the numbers, since they settle part of this. Keep the original post as written when you update it, and add the correction underneath. An edited-away mistake is invisible to the next person who makes it.

42 15VanRx_Mike, steve_okc, dave_SLC and 39 others
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Dr.RheumBOS
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Feb 24, 2026 at 1:26 PM#23

One thing that is still open after Dr.ReproEndo’s answer:

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

43 16cory_ATX, lori_vegas, Dr.PulmRoch and 40 others
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hank_denver
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Mar 1, 2026 at 6:26 AM#24
kate.chem said:
Keep the original post as written when you update it, and add the correction underneath.

I read this differently. The confidence in this thread is running ahead of the evidence, and I would rather the uncertainty were stated than smoothed over because it is unsatisfying.

44 17fiona_VT, denise_HTX, raj_cambridge and 41 others
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mike_nyc
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Mar 5, 2026 at 11:24 PM#25
kate.chem said:
Keep the original post as written when you update it, and add the correction underneath.

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.

45 18CarlaRPh_TPA, steph_laguna, fiona_glasgow and 42 others
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