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Certificates of Analysis: What Proves Purity vs What Proves Nothing
A certificate of analysis (COA) is a document generated by the manufacturer or a third-party lab summarizing analytical test results for a specific batch. Not all COAs verify GHK-Cu cosmetic purity. Most don't. A legitimate GHK-Cu COA includes: (1) HPLC chroma
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- A certificate of analysis (COA) is a document generated by the manufacturer or a third-party lab summarizing analytical test results for a specific batch. Not all COAs verify GHK-Cu cosmetic purity. Most don't.
- A legitimate GHK-Cu COA includes: (1) HPLC chromatogram showing a single peak at 340 Da with ≥95% purity by area under the curve, (2) amino acid analysis confirming 1:1:1 Gly:His:Lys ratio, (3) ICP-MS copper quantification demonstrating 1:1 peptide:copper stoichiometry, (4) batch number and manufacturing date, (5) name and accreditation status of the testing laboratory. The lab should be ISO/IEC 17025 accredited or equivalent. Meaning their testing procedures have been independently validated.
- A worthless COA states 'Purity: ≥98%' without specifying the analytical method, shows no chromatogram, provides no retention time, and lists no amino acid ratios. This is not verification. It's a formality. Some brands generate internal COAs using non-validated methods or visual inspection, which proves nothing about molecular structure. We've seen 'certificates' that declared 99% purity for samples that contained no intact peptide whatsoever when independently tested by HPLC.
- Third-party testing matters because manufacturers have financial incentive to overstate purity. An independent lab with no commercial relationship to the brand has no reason to falsify results. Reputable peptide suppliers like Real Peptides provide third-party COAs for every batch. Not because it's required by law (cosmetic peptides are largely unregulated), but because it's the only way to prove what you're actually selling.