How to Read a Certificate of Analysis (COA)

A Certificate of Analysis (COA) is a lab-issued report of the testing results for one specific batch (lot) of a research compound. It's the single most useful document for verifying what you're actually working with. Here's how to read one.

Identity

The identity test confirms the compound is what the label says it is — usually by HPLC and/or mass spectrometry (LC-MS). Look for a clear "Confirmed" result matching the product name and, where listed, the CAS number and molecular formula.

Purity (HPLC)

Purity is typically measured by High-Performance Liquid Chromatography (HPLC) and reported as a percentage. A COA shows the specification (e.g. ≥95%) and the result (e.g. 99.4%). The result is the share of the sample that is the target compound; the remainder is process-related impurities.

Net peptide content

For peptides, "net peptide content" reports how much actual peptide is in the vial versus salts and residual water. It's usually listed as report only — informational, not pass/fail.

Contaminant screens

Thorough COAs also screen for things that shouldn't be there:

• Heavy metals (ICP-MS) — expect Not Detected
• Endotoxin — a low value such as < 0.05 EU/mL
• Sterility — No Growth
• Fentanyl screen — Not Detected

Why "lot-specific" matters

Purity and content vary batch to batch, so a COA is only meaningful for the exact lot you received. A generic or undated certificate tells you little. Match the lot number on your vial to the lot number on the COA.

Red flags

• No lot number, or a lot that doesn't match your vial
• Missing test date or issuing lab
• "Purity" with no method (HPLC) listed
• A COA that's clearly a stock image rather than a signed report

Bottom line

Every Hexa Research batch is third-party tested, and each order ships with its own lot-specific COA you can open right from the product page. Always verify the lot, the method, and the results before you rely on a compound.

For laboratory research use only. Not for human or veterinary use.