How to read a peptide certificate of analysis

Start with the batch, not the percentage

A certificate of analysis (COA) is useful to an experiment only when it can be linked to the material received. Compare the compound name, reference, batch identifier and report dates with the label and delivery records. A generic specification or another batch’s report does not measure your sample.

Four questions for the document

• Identity: which method was used to identify the compound?
• Result: is the number a batch measurement or a specification limit?
• Unit and method: does it express chromatographic area percentage, mass content or something else?
• Traceability: can you identify the issuing laboratory, report reference and sample?

NIST’s work on peptide quantification compares different methods and highlights the role of the reference material. Do not automatically turn a purity result into an amount of peptide per vial.

A report does not establish everything

The absence of an endotoxin, microbiological or metals result is not a negative result for that test. Ask for the evidence relevant to your research instead of inferring that a quality badge covers every analysis.

At Velia Labs, consult each product’s documentation status. “Testing in progress” does not mean a COA is already available. Contact us if the report your project requires is missing, before selecting a batch for that work. This checklist is not a certificate or an attestation about our inventory.

Further reading

• NIST: comparison of peptide quantification methods
• Eurachem: analytical method validation and fitness for purpose
• HPLC purity and LC-MS identity: what is the difference?
• Documentation questions: contact Velia Labs