What is a COA?
A Certificate of Analysis is the document that certifies a compound has been analyzed by an independent laboratory and meets purity, identity, and quality standards. At BioPeptideX, every batch includes its complete COA.
Why is it important?
Without a third-party verified COA, it's impossible to know whether the peptide has the stated purity, whether the compound really is what it claims to be, whether it contains impurities, or whether it was manufactured under controlled conditions. A supplier without an independent COA is a red flag.
Parts of a COA: what to look for
1. Compound identification
- Compound name.
- CAS number.
- Molecular formula and molecular weight.
- Batch/lot number — must match your vial.
2. HPLC purity
HPLC analysis measures purity through chromatography. You'll see a chromatogram with a main peak (the peptide) and minor peaks (impurities).
Purity levels:
- 99% or higher: pharmaceutical grade — high-precision research.
- 95-98%: research grade — general studies.
- 90-95%: standard — basic research.
- Below 90%: not recommended.
All BioPeptideX peptides have a purity of 99% or higher.
3. Mass spectrometry
This confirms molecular identity. The calculated mass and the found mass should match within 0.5 Da. If they don't match, the compound isn't what it claims to be.
4. Appearance
It should read "White to off-white lyophilized powder". Unusual coloring indicates degradation.
5. Water content
It should be under 5%. A high value indicates poor lyophilization.
6. Issuing laboratory
It should be independent from the supplier, accredited under ISO standards, and include the analyst's name and signature.
Red flags: COAs you shouldn't accept
- COA issued by the same supplier that sells the peptide.
- No batch/lot number.
- No visible HPLC chromatogram.
- No mass spectrometry confirmation.
- Analysis date older than 1 year.
Conclusion
Knowing how to read a COA is essential for any researcher. At BioPeptideX, COA transparency is our minimum standard.