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Purity, sterility, and Certificates of Analysis

Why '99% pure' on a COA does not mean 'safe'.

A Certificate of Analysis (COA) reports analytical results for a batch — typically identity and chemical purity, often measured by HPLC and mass spectrometry. These are useful chemistry checks.

But chemical purity is not the same as sterility or safety. A preparation can be chemically pure yet contaminated with bacterial endotoxin, mislabeled, degraded, or simply never tested for human use. High-purity claims address one narrow question and say nothing about clinical safety.

This is why gray-market 'research-use-only' material carries real, under-appreciated risk, independent of any purity figure printed on a certificate.

Educational and research reference only. Not medical advice.

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