Verify a peptide COA lot number yourself

A certificate of analysis only means something if you can independently tie it to the vial in front of you. Here is the procedure a research lab can run in a few minutes, without taking the supplier's word for any of it.

1. Match the lot number on the vial to the COA

The single most common failure is a generic COA stapled to a different lot. Check whether the report names a lot number or an assigned reference. Some Pure North reports use assigned references that differ from photographed vial codes. Request the documented sample-to-lot mapping before treating a differing reference as a match.

2. Confirm the issuing lab

Pure North commissioned Canada Peptide Testing, as a paying client. Published reports cover RP-HPLC-UV area purity and measured content for named samples and vial sizes. They do not include mass-spectrometry identity, endotoxin, sterility or water-content results. Read the original documents at Lab Results.

3. Read the two numbers that matter

Our published reports give HPLC-UV area purity and measured content. They do not contain mass-spectrometric identity, sterility or endotoxin results. Results apply to the sample tested, and manufacturer QC documents are separate. Read our HPLC vs LC-MS guide for the distinction.

4. Cross-check against the lot archive

Pure North publishes laboratory reports for the samples and vial sizes listed in Lab Results. Each report identifies its method, reference, area purity and measured content. Open the matching product page to check coverage for the size you select. A report does not cover every size or future lot; contact customer service if your vial reference differs. Bacteriostatic water has no COA.

5. Use the verification page

Open the Retatrutide laboratory record alongside the published PDF. Compare report number, version, size, reference, dates and results. Retain the complete report and its reporting statements. Read our annotated report walkthrough for an example.