Peptide COA Library
Third-party peptide COAs for Peptryn research peptides: HPLC purity, identity by mass spectrometry and, where tested, endotoxin, run by MZ Biolabs and linked to the lab’s own reports.
How this peptide COA library works
Each certificate here is for one production lot of a Peptryn research peptide. MZ Biolabs, an independent lab in Tucson, Arizona, ran the tests using HPLC-UV-MS. A certificate page shows the lot, the HPLC purity and either an endotoxin result or an identity confirmation, and links to the report hosted on MZ Biolabs’ own site.
- 19 certificates for 17 products
- HPLC purity from 99.11% to 99.97% across the published lots
- 15 certificates with an endotoxin result, all negative
- 4 with identity confirmation instead: Retatrutide 30mg, KPV 5mg, KPV 10mg and Tirzepatide 30mg
Peptryn sells these peptides for laboratory research only, to buyers who are 21 or older. A certificate describes the lot it names, so match the lot on your vial to the lot on the page.
Published reports
Lot 2026-07-07 · Purity 99.78% · Endotoxin: Negative
Lot 2026-07-07 · Purity 99.74% · Endotoxin: Negative
Lot 2026-08-05 · Purity 99.86% · Endotoxin: Negative
Lot 2026-08-05 · Purity 99.93% · Endotoxin: Negative
Lot 2026-08-05 · Purity 99.75% · Endotoxin: Negative
Lot 2026-08-05 · Purity 99.13% · Endotoxin: Negative
What a peptide COA tells you, and what it does not
A certificate of analysis (COA) is a lab report for one batch. It names the lot, lists the tests that were run and gives the results. It tells you about that lot. It does not tell you about other lots, how the product was stored after testing, or anything a test did not cover.
| Result | What it shows | Where it appears |
| HPLC purity | The main peak’s share of all detected peaks at one wavelength. It does not measure how much peptide is in the vial. | All 19 certificates |
| Identity (mass spectrometry) | That the main peak has the expected mass for the compound. | All 19 certificates |
| Endotoxin | A bacterial endotoxin result for the lot. | 15 of 19, all negative. Not listed for Retatrutide 30mg, KPV 5mg, KPV 10mg or Tirzepatide 30mg. |
| Quantity per vial | The measured amount of peptide, which is a separate test from purity. | Listed on the Retatrutide 30mg certificate page. For other lots, open the lab’s report and look for a quantity line. |
| Purity and identity report on the lab’s own site | A copy of the result you can open without relying on Peptryn’s page. | Linked from all 19 certificate pages, with a QR code on each certificate. Endotoxin reports are PDFs shown on the certificate page |
Our guide to reading a certificate of analysis walks through a real report line by line, and peptide purity explains what a high percentage can hide.
How to verify a peptide COA
- Open the certificate page for your product and size, and note the lot.
- Match that lot to the label on your vial. Check that the analysis date fits the lot date.
- Click through to the report on MZ Biolabs’ own site, or scan the QR code on the certificate, and compare the purity and lot with the page.
- Check which tests are listed: identity, endotoxin and quantity are not on every report.
- If your lot is not published or a test you need is missing, email us your order number and we will send the report on file.
Third-party tested peptides: what the phrase should mean
“Third-party tested” should mean an independent lab ran the test, the report names your batch, and you can open the report on the lab’s own site. Many sellers use the phrase for a PDF they host themselves. Our Janoshik and Finnrick guides explain how independent testing services work and what each one can and cannot show, and peptide testing covers the methods. The third-party tested peptides guide sorts the claim into five levels of proof.
Peptide COA questions
What is a peptide COA?
A peptide COA, or certificate of analysis, is a lab report for one batch. It lists the lot, the tests run and the results, such as HPLC purity and identity by mass spectrometry. It describes that lot only, so match the lot to your vial.
Are Peptryn’s peptides third-party tested?
The 19 lots in this library were tested by MZ Biolabs, and each certificate page links to the report on the lab’s own site. Products without a certificate here have no published report yet. Email us with your order number to ask for the report on file.
Who tests the certificates?
MZ Biolabs, an independent lab in Tucson, Arizona. The method on every certificate is HPLC-UV-MS.
How do I verify a Peptryn COA?
Open the certificate page, match its lot to your vial, and click through to the report on MZ Biolabs’ own site or scan the QR code on the certificate. Compare the purity and lot on the lab’s report with the page.
Do the certificates include endotoxin results?
15 of 19 do, and all of those read negative. Retatrutide 30mg, KPV 5mg, KPV 10mg and Tirzepatide 30mg report identity confirmation instead.
What purity do the published lots show?
HPLC purity ranges from 99.11% (CJC-1295 no DAC, lot 2026-08-05) to 99.97% (Tesamorelin and Tirzepatide 30mg). Purity is the main peak’s share of detected peaks, not the amount of peptide in the vial.
Does a COA say how much peptide is in the vial?
Not by itself. Quantity is a separate result from purity. The Retatrutide 30mg certificate page lists it, and other lab reports may include a quantity line, so open the lab’s report and look. If you need it for a specific lot, ask before you order.
Can I get the COA for my specific lot?
Yes. If your lot is not published here, email us with your order number and we will send the current report on file.
Testing in progress
Every production batch we ship undergoes third-party testing at MZ Biolabs before it’s sold, but we only publish a certificate here once that report is back and lot-matched. We’re actively working through the rest of the catalog and will add each report as it clears testing.
Products without a published certificate yet: AHK-Cu, Cagrilintide, Epitalon, Kisspeptin-10, NAD+, Pinealon, Selank and Semaglutide.
If you need the certificate for your specific lot before it’s published here, email us at [email protected] with your order number and we’ll send the current report on file.