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Know what's really in the vial
Plain-language guides to reading, checking, and trusting peptide Certificates of Analysis — so you can tell a real report from a forged one before you buy.
How to Read a Peptide COA: A Beginner's Guide
Four things every COA should tell you — purity, identity, batch number, and the testing lab — and how to check each one in five minutes.
ChecklistWhat Should a Legitimate Peptide COA Include?
Every field a real Certificate of Analysis should contain — identity, lot number, lab details, methods, purity spec, net peptide content — and the red flag when one is missing.
Red flag, explainedWhy "100% Purity" on a COA Is a Red Flag
It reads like the best possible result. It's actually the strongest sign the number wasn't measured — the chemistry and instrumentation behind why real HPLC never lands on exactly 100%.
Compound guideHow to Read a Tirzepatide COA
The verified molecular weight, how to tell tirzepatide from semaglutide or retatrutide on a mass spectrum, and the red flags specific to GLP-1/GIP certificates.
Compound guideHow to Read a Semaglutide COA
The verified molecular weight, how to tell semaglutide from tirzepatide or retatrutide on a mass spectrum, and the red flags specific to GLP-1 certificates.
ReferencePeptide Molecular Weight Reference Table
Verified monoisotopic and average masses for 51 research compounds — and how to use them to check whether a COA really describes the peptide it names.
The numbersPurity vs Net Peptide Content
A peptide can be 99% pure and still be only 72% peptide by weight. Why the two numbers differ, and how to calculate what's actually in the vial.
FundamentalsWhat Is a Certificate of Analysis (COA)?
What a COA actually proves, the critical difference between third-party and in-house testing, and what a genuinely good one contains.
VerificationHow to Spot a Fake Peptide COA: 12 Red Flags
A forensic checklist for catching photoshopped certificates, reused chromatograms, impossible purity numbers, and untraceable labs.
ReferenceResearch Peptides (RUO): The Complete Buyer's Guide
Synthesis, purity grades, analytical testing, storage, and a rapid vendor-triage checklist for the research-use-only market.
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