What a certificate of analysis actually tells you
How licensed practices should read a certificate of analysis (COA) for peptides and other compounded or specialty products: identity, purity, lot matching and red flags.
A certificate of analysis, or COA, is the document that says a specific lot of product was tested and what the results were. For licensed practices purchasing peptides and other specialty products, it's the single most important piece of paper in the shipment.
Who issued it
A COA should come from an independent, accredited laboratory, not from the seller's own letterhead. The lab name, address and accreditation should be on the document, and the lab should be reachable to confirm the report.
Lot matching
The lot number on the COA must match the lot number on the vial or package in your hand. A COA for a different lot, or with no lot number at all, tells you nothing about what you received.
Identity
Identity testing confirms the product is what the label says it is, typically by mass spectrometry. Look for the measured mass and the expected mass side by side.
Purity
Purity is usually reported as a percentage from high-performance liquid chromatography (HPLC). The report should include the chromatogram, not just a number, and state the method. Be skeptical of round figures like "99%" with no supporting data.
Other tests
Depending on the product, a full COA may include endotoxin, sterility, residual solvent, water content and heavy-metal results. The tests that apply depend on the product and its intended handling; a supplier should be able to explain why each test is or isn't present.
Red flags
- No lab name or an unverifiable lab.
- No lot number, or a lot that doesn't match the product.
- A number with no chromatogram or method behind it.
- A report dated years before the product's manufacture.
- A supplier who can't produce a COA on request.
Keeping records
File COAs with the receiving record for each lot. When a product is used or discarded, the COA stays in the file for the retention period your license requires.
ClinicSupply US attaches a lot-matched COA to every shipment of specialty products and keeps a copy in your account history. Ask about the verified-provider program.