Every batch of a research peptide should come with a certificate of analysis (COA) — the document that tells you what is actually in the vial. But a COA is only useful if you know how to read it. This guide walks through the key sections, for in-vitro laboratory research only.
What a COA is
A certificate of analysis is a batch-specific report produced by an analytical laboratory. It records the tests performed on a particular lot of material and their results. Because it is batch-specific, a COA describes the exact batch you received — not a generic product.
HPLC purity
High-performance liquid chromatography (HPLC) separates the components of a sample so their relative amounts can be measured. On a COA, the HPLC result is usually expressed as a purity percentage — for example, ≥ 99%. This tells you what proportion of the material is the target compound versus impurities. The higher the purity, the fewer unknown substances are present.
Mass-spectrometry identity
Purity tells you how much of the sample is a single compound, but not which compound it is. That is what mass spectrometry (MS) is for. MS measures the molecular weight of the material and confirms that it matches the expected weight of the target peptide. A COA that reports both HPLC purity and MS identity is confirming two things: how pure the material is, and that it is the correct compound.
Other details to check
- Batch / lot number — should match the vial you received.
- Compound name — should match what you ordered.
- Test or release date — shows when the batch was analysed.
- Testing laboratory — an independent, third-party lab adds credibility versus in-house-only testing.
Why third-party testing matters
A supplier that tests its own material has an inherent conflict of interest. Independent, third-party testing removes that. Every Helixa Biotech batch is tested by Testides and Peptide Test Canada, an independent laboratory, for HPLC purity and MS identity. See our Research & Quality page for more on our testing process.
Research Use Only. All products supplied by Helixa Biotech are sold strictly as reference materials for in-vitro laboratory research and are not for human or animal consumption. Nothing in this article is medical advice.