A Certificate of Analysis (COA) proves a research peptide's quality — but only if you know how to read it. This beginner's guide walks through the parts of a COA and what each one tells you.
First, What a COA Is
A COA is a lab document reporting the test results for a specific batch of a compound. It's the evidence behind claims like "99%+ purity." Reading it correctly lets you verify a product instead of just trusting the label.
The Parts of a COA
1. Batch / Lot Number
This should match the batch you received. A COA is only meaningful if it corresponds to your actual vial — not a generic or old batch. Always check this first.
2. Product Name and Details
Confirm the compound name, and where listed, its molecular weight or sequence details. These should match what you ordered.
3. HPLC Result (Purity)
This is the purity figure — look for 99%+. The COA may include a chromatogram (a graph with a large peak for the target compound). A single dominant, clean peak indicates high purity.
4. Mass Spectrometry Result (Identity)
This confirms the compound is what it claims to be, by matching its measured molecular weight to the expected value. Purity without identity is incomplete — you want both.
5. Testing Date and Laboratory
Check when the testing was done and, ideally, that it was performed by an independent third-party lab rather than self-reported.
Red Flags to Watch For
- No batch number, or a batch number that doesn't match your order.
- Only a purity claim with no supporting chromatogram or data.
- No identity (mass spec) confirmation — purity alone isn't enough.
- A supplier that can't produce a COA for your specific batch at all.
A Simple Checklist
- ✅ Batch number matches my order
- ✅ Product name/details are correct
- ✅ HPLC shows 99%+ purity
- ✅ Mass spec confirms identity
- ✅ Testing date and lab are shown
Key Takeaways
- A COA is only valid if its batch number matches your actual vial.
- Check HPLC (purity, 99%+) and mass spec (identity) — you want both.
- Confirm the testing date and an independent lab.
- If a supplier can't provide a matching COA, that's a red flag. Research use only.
Every Helio Peptides batch comes with a Certificate of Analysis — third-party tested to 99%+ purity by HPLC and mass spectrometry, made in the USA. Browse our research peptides →
Disclaimer: All products are intended solely for laboratory research and are not for human or animal consumption. These statements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease.