PharmacoVig_BOS said:I tested my certificates of analysis batch through Janoshik — 97.3% purity.
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.
carlos_SATX said:Agreed, and mass spec answers a question purity does not: identity.
This is exactly what I could not find anywhere else. Taking it to my next appointment.
PharmacoVig_BOS said:I tested my certificates of analysis batch through Janoshik — 97.3% purity.
My vendor review relevant to certificates of analysis: ordered 4 times from my current compounder. Consistency has been excellent.
Shipping: 2-day priority with gel ice
Packaging: Professional, discreet, proper labeling with lot/batch numbers
Purity: 99.5% average across orders (Janoshik verified)
Customer service: Responsive within 4 hours
Price: $133/month for semaglutide 1.7mg equivalent
Sigma-Aldrich — Research-Grade Standards
Certified reference materials, analytical reagents, and research-grade standards for peptide verification. Trusted by laboratories worldwide.
Shop Reference Standardsnewstart_MO said:Two reports on the same product from two laboratories, four percentage points apart, and no method stated on either.
My HPLC chromatogram analysis for certificates of analysis — I sent my batch to Janoshik and here's what the results showed:
Main peak retention time: 15.4 minutes (consistent with semaglutide reference standard)
Peak purity: 98.4%
Related substances: 0.6% (single impurity at 9.4 minutes — likely a synthesis intermediate)
Mass spec: m/z 4113.6 (matches expected molecular weight)
This is a clean result. The mass spec confirmation is particularly important — it proves the molecule is actually semaglutide and not a substitution.
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