What Is a CoA and Why Is It the Only Real Proof of Peptide Purity
Every researcher ordering peptides faces the same problem: you cannot visually determine the difference between a peptide of 78% purity and one of 99% purity. Both look identical — a white or cream lyophilisate in the vial. The only real proof you have is the Certificate of Analysis.
The CoA is not a marketing document. It is an analytical report specifying what is actually in the vial you ordered. Without it, you are working with an unknown variable at the centre of your experiment.
What a CoA Must Contain
Compound identification — name, CAS number, molecular formula. Confirms you are receiving what you ordered.
Batch number — a unique identifier for every production run. Essential for reproducibility: if results vary between repeated experiments, the batch number lets you identify whether the material changed.
Analysis method — HPLC is the standard. A supplier that does not specify the method is not making a verifiable purity claim.
Measured purity — >99% means less than 1% impurities. 95% means 5% potential contaminants — significant depending on experimental design and method sensitivity.
Date of analysis — peptides degrade over time. A CoA without a date tells you nothing about the current state of the material.
Why Some Suppliers Don't Include CoA Automatically
Two reasons. Either they don’t have one because they don’t analyse every batch systematically, or they have one but use it as a negotiating point — available on request or for premium orders only. Neither is acceptable for a researcher who needs reproducible results.
The Cellmind Approach
Cellmind attaches the CoA to every order automatically — no request, no additional cost, no exceptions. Every vial carries a serial number traceable to the original analytical report from an EU-certified laboratory.
- CoA with every order without exception
- HPLC verification for every batch
- Serial number on every vial
- EU-certified laboratory
For orders: staging.bycellmind.com
