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ForumsCOA & Analytical TestingJanoshik vs in-house testing — third-party verification importance Page 4

Janoshik vs in-house testing — third-party verification importance

PurityPaulOR Sat, Jun 6, 2026 at 8:54 PM 18 replies 263 viewsPage 4 of 4
Dr.RheumBOS
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Jun 8, 2026 at 2:36 AM#16

Clinical perspective, offered as context rather than as advice.

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.

43 16pam_stl, wei_SG, cory_ATX and 40 others
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amsterdam_pete
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Jun 8, 2026 at 6:56 AM#17

A narrower follow-up, since the general answer is now clear:

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

44 17ZaraB_AL, JakeSmashed95, NauseaFreeNow and 41 others
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hannah_MT
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Jun 8, 2026 at 11:16 AM#18
Dr.RheumBOS 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…

My vendor review relevant to certificates of analysis: ordered 6 times from my current compounder. Consistency has been excellent.

Shipping: 3-day with temperature monitor
Packaging: Professional, discreet, proper labeling with lot/batch numbers
Purity: 98.3% average across orders (Janoshik verified)
Customer service: Responsive within 1 hours
Price: $123/month for tirzepatide 10mg equivalent

45 18MaxMetOK, MounjBrad, nick_newbie and 42 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
andrew_nyc
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Apr 2024
New York, NY
Jun 8, 2026 at 3:35 PM#19
Dr.RheumBOS 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…

HPLC results interpretation for certificates of analysis: when you get your Janoshik report back, here's what the numbers mean:

  • Purity %: Should be >97%. Below 95% is concerning.
  • Retention time: Should match reference standard for the peptide
  • Related substances: Degradation products should be <2% total
  • Single impurity: No individual impurity should exceed 1%

My last batch: 99.7% purity, 0.1% total related substances. Clean chromatogram with single sharp peak at expected retention time. Exactly what you want to see.

46 19julia.endo, JessicaM_2024, TomFromTexas and 43 others
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Admin
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Jun 8, 2026 at 7:55 PM#20

Moderator note: a post naming a supplier has been edited. Discuss suppliers in the review sections, not here. No action needed from anybody.

18 16PeptideSynthNJ, Dr.KarenChen, Dr.NateNeph and 15 others
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