QUALITY & TESTING

Reading an HPLC Certificate of Analysis

Velox Peptides Research Team·Published May 2026·6 min read
For in vitro research use only. This guide is provided for scientific reference to help researchers interpret batch documentation. All Velox Peptides compounds are supplied for in vitro research use only.

What is a Certificate of Analysis?

A Certificate of Analysis (CoA) is the document that accompanies a research compound and reports the results of the laboratory tests performed on that specific batch. It is the primary evidence of what is actually in the vial — identity, purity and physical form — and a genuine CoA should always be tied to a specific batch or lot number, not the product in general.

Every Velox Peptides compound is third-party HPLC-tested, with batch documentation available on request. This guide explains how to read the key sections.

What HPLC purity actually means

HPLC (High-Performance Liquid Chromatography) separates the components of a sample and measures the proportion of each. On a CoA, “HPLC purity” is the percentage of the sample that is the target peptide, with the remainder being related impurities, truncated sequences or residual synthesis reagents.

A figure such as “≥98% HPLC purity” means at least 98% of the material is the intended compound. The accompanying chromatogram — the graph of peaks — should show one dominant peak for the target, with only small secondary peaks. A reputable CoA shows the chromatogram, not just the number.

Why mass spectrometry confirmation matters

HPLC tells you how much of the sample is a single compound, but not which compound. Mass spectrometry (MS) answers the identity question by measuring the molecular weight of the peptide and confirming it matches the expected value for the target sequence.

A CoA that reports both HPLC purity and an MS-confirmed molecular weight gives you two independent assurances: that the material is pure, and that it is the correct molecule. Purity without identity confirmation is only half the picture.

What to check on any CoA

Look for: a specific batch/lot number; the testing laboratory named (ideally an independent third party); the HPLC purity figure with a visible chromatogram; an MS-confirmed molecular weight; the appearance and form (e.g. white lyophilised powder); and a test date. Be cautious of documentation that lacks a batch number, names no laboratory, or shows a number with no underlying chromatogram.

You can review Velox Peptides batch documentation in the CoA library, or read more about our testing process on the Quality & Testing page.

Frequently asked questions

What does HPLC purity mean on a CoA?
It is the percentage of the sample that is the target compound, as measured by High-Performance Liquid Chromatography. ≥98% means at least 98% of the material is the intended peptide.
Why does mass spectrometry matter?
HPLC shows how pure a sample is but not what it is. Mass spectrometry confirms the molecular weight matches the target sequence, verifying identity.
Should a CoA be batch-specific?
Yes. A genuine CoA reports results for a specific batch or lot number, not the product in general.
Where can I see Velox Peptides CoAs?
Batch documentation is available on request and archived in the CoA library. Every order includes a batch-specific certificate.
Compliance statement. Velox Peptides supplies research reagents for in vitro use by qualified researchers. Every compound is sold strictly as a research reagent. No product is a medicinal product within the meaning of the Human Medicines Regulations 2012. No product has been evaluated by the MHRA or FDA. No product is intended for human or veterinary consumption, diagnosis, treatment, cure, or prevention of any condition. Any use outside lawful scientific research is outside the scope of sale. See our Research Use Policy and MHRA Statement.

All research summaries on this page are derived from publicly available peer-reviewed literature. Velox Peptides makes no therapeutic claims. For research use only.