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How we vet every compound

Reading a Certificate of Analysis

Every vendor we link to publishes a third-party lab report. But not all reports test the same things — and a high purity number alone tells you almost nothing. Here is what we actually look for, and how our vendors compare on the same compound.

The panel

What a certificate should prove

A complete report answers five separate questions. Most COAs answer two or three. Knowing which is missing is the whole point.

01 · Identity

Is it the right molecule?

Mass spectrometry (LC-MS/MS or MALDI) weighs the peptide to confirm its exact mass. A chromatography-only "reference match" compares peak timing — weaker evidence.

02 · Purity

How much is the peptide?

RP-HPLC separates the sample and reports the percentage that is the target compound versus everything else. Look for a single sharp peak.

03 · Content

Is the vial filled right?

Quantitation measures the actual milligrams present, not just purity. A 99% pure vial that is underfilled still shortchanges the buyer.

04 · Safety

Is it contaminated?

Endotoxin, heavy metals, sterility, and adulterant screens catch what purity can't: bacterial toxins, metals, microbes, and dangerous cutting agents.

05 · Provenance

Can you trust the paper?

An accredited lab, a signed chemist, a web-verifiable code, and tamper-evident marks are what separate a real report from a printed graphic.

The full roster

Every vendor, one compound

We benchmarked on Retatrutide because every vendor carries it, so the reports are directly comparable. Each row is a real published document we read line by line. Vendors are listed alphabetically — this is a map of what each report proves, not a ranking.

Assay Comparison — RetatrutideMarks reflect the published reference report
VendorLabIdentityPurityContentEndotoxinMetalsSterilityVerifiable
American PeptidesBioviridiansignedMass spec99.8–99.9%YesYesYesSigned · QR
ApolloJanoshikblind99.90%YesVerify key
EvolveMZ Biolabs+ JanoshikMass spec99.5–99.97%YesVerify key
IgniteILS LabsISO 17025 accreditedConfirmedRP-HPLC UV99.35%Yes · 10.49mgYesYesYes+ fentanyl screenYes
LimitlessIn-house + 3rd-partyon requestMass specstated>99% (stated)On request
Mile HighChromate / Kovera / ILSConformsRP-HPLC UV99.09%Yes · 10.31mgYesYesKovera batchesYes
Peak LabBioviridianCollege Station, TXMass spec99.7%YesBatch-verified
PSPeptides3rd-partyAustin, TXMass spec99.93%YesYesYesYes
Yes shown on the report not on this reportRed accreditation stated on the certificate

—  Limitless provides its certificate on request rather than posting it publicly; its standard certificate covers identity and purity.

—  PSPeptides documents its data across three separate public reports per batch: certificate (identity, purity, content), endotoxin, and heavy metals.

How to read this

What the marks mean

No single certificate here covers every test — each vendor documents a different combination, and a strong purity figure on its own answers only one of the five questions above. A filled mark means the test appears on that vendor's published report; a dash means it does not. Use the table to see which questions a certificate answers, then obtain the current lot-specific document from the vendor before you buy.

As reviewed 28 August 2026.The certificate details summarized here reflect each vendor's published Certificate of Analysis as reviewed by Aura Protocols on the date shown. A Certificate of Analysis is issued per production lot; testing laboratories, methods, and results may differ for other lots and may be changed by a vendor at any time without notice. Aura Protocols does not perform, commission, or control this testing and assumes no responsibility for any subsequent change to a vendor's COA methods, results, or availability, nor for the accuracy of any vendor-issued document. Always obtain and review the current lot-specific Certificate of Analysis directly from the vendor before purchase. For research use only — not for human consumption; the compounds referenced are not approved by the FDA to prevent, treat, or cure any disease. Aura Protocols does not manufacture, test, or sell these compounds.