How to read a COA (lab report)

What a COA is

A Certificate of Analysis, or COA, is a lab report that records the results for one tested sample. It typically answers three questions: what the compound is (identity), how pure it is (purity), and how much material the sample contains (quantity). A COA describes the sample that was tested; it does not by itself prove anything about other vials, batches, or listings, but the story changes when batch numbers are introduced and batch conformity is proven, but more on that later.

Laboratory name and report date

Start at the top of the report. A credible lab report names the laboratory that performed the test and shows the date the work was done or the report was issued. Confirm that the report date is consistent with the age of the batch you are checking: a report dated before the batch was produced cannot describe that batch. A report that hides the laboratory or shows no date cannot be checked against anything.

Peptaura does not require a particular laboratory: you may pick any reputable lab that is accessible to you. The laboratories Peptaura endorses are Finnrick, Janoshik, Chromate, Kovera Labs, TrustPointe Analytics and Uzorak.

Identity: mass spectrometry

Identity testing answers whether the material is the compound it claims to be. Mass spectrometry (MS) measures the molecular weight of the sample; the measured mass should match the mass of the labeled compound. Look for an MS result that names the compound and shows the measured value, not just a line that says a test was performed.

Purity: HPLC

Purity is usually measured by high-performance liquid chromatography (HPLC). The report should name the method and show a numeric result with its unit, commonly a percentage. Many reports include the chromatogram behind the figure. A purity number without a stated method or unit cannot be compared with anything else, and a rounded marketing figure is not the same as a measured result.

Quantity and content

Quantity or content results report how much of the compound the sample contains, in units such as milligrams per vial or milligrams per millilitre. Compare the measured quantity with the amount claimed on the label or listing. A report that shows a result without units leaves the figure unverifiable.

Endotoxin

Endotoxins are components of the outer membrane of certain bacteria that can remain in a sample even when no live bacteria are present. They are typically measured with the LAL (Limulus amebocyte lysate) test and reported in endotoxin units (EU), usually per milligram (EU/mg) or per vial (EU/vial). Read the result against the limit stated on the report: first check that the result and the limit use the same unit, then check that the result is below the limit. A result without a unit cannot be compared with anything.

Sterility

A sterility test checks whether microorganisms grow from the tested sample when it is incubated in culture media, following a compendial method such as USP <71> (United States Pharmacopeia). The result is usually reported as pass or fail, or as growth or no growth. A pass means no microbial growth was detected in the sample that was tested.

Heavy metals

Heavy-metal testing is generally not needed. All longer peptides produced using SPPS (solid-phase peptide synthesis) or hybrid methods will have trace amounts because of the resin, but in Peptaura’s experience these are well under safety guidelines. Shorter peptides synthesized strictly via LPPS (liquid-phase peptide synthesis) will not.

Matching the batch number

The batch number printed on the report should match the batch number on the vial or on the listing. If the numbers differ, the report describes a different batch and does not cover the product in front of you. When a listing or vial shows a batch number, the batch verification page shows the published records and reports linked to that batch, including matching COAs and any quality or recall notice. A missing record is not the same as a passing result.

Batch numbers are what allow one report to speak for more than a single vial. On Peptaura, every batch number a vendor publishes is stored in a permanent verification record tied to that vendor and product, and it stays in the record after the batch stops being sold. A batch number cannot be reused by another vendor, and a vendor cannot use it for a different SKU; only package sizes of the same SKU may share a batch. Batch conformity is then proven through the COAs linked to that batch number. Only reports that cover identity, purity and mass count, and Peptaura cross-references the vendor’s own reports with customer-submitted, Peptaura-submitted and group-tested reports, and with other doses from the same production batch. How much of that evidence exists is what the batch shield shows.

Batch shields

Next to a published, active batch number, Peptaura can show a batch shield. A shield appears only when the batch is linked to COA evidence for that exact dose or for its batch group, meaning the same vendor’s production batch of that compound across doses. Only reports that include identity, purity and mass testing count; endotoxin-only and other partial reports are still listed but do not earn a shield. A recalled batch shows a warning instead of a shield.

Bronze means at least one COA from the vendor, a customer, Peptaura or a group test exists for the batch group, for any dose.

Silver means the vendor’s COAs cover this dose and another dose in the same batch group.

Gold means the batch group has both vendor COA evidence and customer-submitted, Peptaura-submitted or group-tested COA evidence.

Platinum means this exact dose and batch have both vendor COA evidence and customer-submitted, Peptaura-submitted or group-tested COA evidence.

Green means the vendor follows the golden standard of testing, with multi-vial identity, purity, mass and endotoxin testing on all deterministic batches.

You can see a batch’s shield and the reports behind it on the batch verification page.

Group testing

Group testing lets buyers pool money to have a product tested by an independent laboratory. On the testing page, anyone can request a test or join a pool for a verified Peptaura batch, or for a compound whose batch number is entered manually or left blank. Each pool shows the laboratory, the tests, the minimum contribution and how much of the target has been funded.

If a pool is not funded within 30 days, every participant is refunded. Once it is funded, vials are sent to the laboratory and the results are published as COAs. When the tested product has a Peptaura batch, the result is linked to that batch and counts as group-tested evidence toward its batch shield.

One person can also pay for 100% of a test on their own instead of pooling: when creating a pool, choose to pay for the test in its entirety, which also means sending every vial the test needs. Tests ordered through Peptaura are cheaper because Peptaura has partnered with the laboratories that perform them.

Red flags

Treat any of these as a reason to look closer rather than to accept the report: a missing laboratory name or report date; a batch number or compound name that does not match the vial or listing; a report dated before the batch it is presented for; a report that looks edited or that the laboratory cannot confirm; a purity figure without a named method; and results with no units. None of these alone proves a problem, but each one removes a check that makes the report meaningful.

Where to check reports

The public COA directory lists published reports with the compound, vendor, dosage, report date, batch information, and test type next to the original document. The batch verification page looks up records by batch number. Anyone can submit a report through the COA submission page using a source link or an uploaded file. For an overview of how these pieces fit together, see How Peptaura verifies quality.