How to Verify Peptide Quality: Testing, Purity, COAs and Supplier Transparency

A Certificate of Analysis, commonly called a COA, is one of the most important documents researchers can examine when evaluating laboratory materials.

A peptides COA generally records analytical information for a particular manufactured batch.

Depending on the material and laboratory, the certificate may include:

• Compound name
• Peptide sequence
• Molecular formula
• Molecular weight
• CAS number
• Batch number
• Manufacturing date
• Testing date
• HPLC purity
• Mass spectrometry
• Net peptide content
• Additional laboratory testing

Researchers reviewing a peptide Certificate of Analysis should first determine whether it corresponds to the exact batch being evaluated.

Batch-Specific COAs Are Important

Peptide testing results should be connected to the material tested.

This is why the batch or lot number matters.

Researchers should compare the lot number shown on the laboratory report with the batch identification associated with the material.

If they do not match, the analytical report may not describe that particular batch.

A good research peptide COA therefore provides traceability between:

1. The peptide
2. The batch
3. The laboratory test
4. The analytical results
5. The Certificate of Analysis