Peptide lab tests & purity database

Dataset at a glance

Download & cite

The full dataset is available as an open download in two formats. Version 1.0, released under the CC BY 4.0 license. Last updated 2026-03-20.

How peptide purity is verified

Every record on this page reports purity from high-performance liquid chromatography : the standard analytical method for synthetic peptides. The most rigorous tier is a per-lot certificate of analysis: a single document tied to a specific production batch, generated by an independent third-party laboratory, listing the lot number, test date, and integrated peak purity percentage. We tag those rows with a Per-lot COA badge.

Vendors that publish only a marketing-grade purity claim (no per-batch document) appear as Vendor spec rows. Both are useful for visitors comparing vendor coverage, but per-lot COAs carry meaningfully more analytical weight. We do not run the lab work ourselves; each row links out to the vendor's published source so you can verify the document against the lot you receive.

For the underlying chemistry of how solid-phase peptide synthesis produces these purity profiles, see our injectable vs oral peptides bioavailability guide.

Methodology

Inclusion criteria

We list research peptide vendors that publish purity data we can point to directly, either a per-batch certificate of analysis or a stated HPLC specification on a public page. Vendors are included for coverage breadth and disclosure quality, not because they pay us. Two of the 6 vendors here are affiliate partners; the other four are listed editorially so readers can compare disclosure side by side. A vendor with no public purity claim at all is not listed, because there is nothing to verify.

Verification tiers

Every record carries one of two tiers. Per-lot COA means the vendor publishes a public per-batch certificate that names the lot number, the exact purity percentage, and the test date, which we link directly on the row. Vendor spec means the vendor states a purity target (for example ≥99% HPLC) on a product or lab page without a per-lot certificate. Vendor spec is the clearly lower trust tier: it is a claim about process, not a document tied to the vial you receive.

Provenance

Each per-lot record links to the vendor's own COA image or PDF (or, where we self-host a copy, to the certificate we saved from that source). We transcribe the lot number, purity percentage, and test date from those certificates into a structured row. We do not run the assays, and we do not certify the numbers. The linked certificate is the source of truth; if a transcribed value ever disagrees with the linked document, the document wins.

Conflict of interest

We have affiliate relationships with some of the vendors listed here and earn a commission when readers buy through our links. That relationship does not change the transcribed purity, lot, or test-date values on this page, because those values come from the vendors' own published certificates, not from us. Records from partner and non-partner vendors are held to the same tiering rules. For the full disclosure, see our affiliate disclosure.

Update log

• 2026-07-11

  Dataset formalized: added downloadable CSV and JSON distributions, Dataset schema version and citation, and this update log.

• 2026-04-29

  Added the Sports Technology Labs per-lot COA set and Synthrolab per-batch certificate library.

Vendors covered

We index public certificates of analysis from 6 research peptide vendors. Two are partner vendors with a discount; the others are listed editorially so visitors can compare vendor disclosure side-by-side.

Frequently asked questions

Glossary

COA (Certificate of Analysis)

A laboratory document that certifies the analytical properties of a specific batch of material, including its purity, identity, and test method. The per-lot version is the trust anchor for research-grade peptides.

HPLC (High-Performance Liquid Chromatography)

The standard analytical technique for determining the purity of a synthetic peptide by separating the target molecule from impurities and measuring the resulting peak area.

Lot / Batch

A unique identifier for a specific production run. Per-batch COAs are tied to this number, which should match the vial label on what you receive.

Third-party lab

A laboratory unrelated to the vendor that runs the analysis independently. Vendor self-testing is meaningfully weaker evidence than third-party testing.

Per-lot COA vs Vendor spec

Per-lot COA = a public per-batch certificate document. Vendor spec = a marketed purity claim on the product page without a per-batch document. Both appear in this database with clear badges.