Evidence review: Open Peptide Project (verified against primary PubMed, ClinicalTrials.gov & FDA records) · Last checked 2026-10-27. ← Back to Evidence Library

How blind retail batch testing works: the Open Peptide Standard chain of custody

Name: How blind retail batch testing works: the Open Peptide Standard chain of custody
Published: 2026-10-27

Why the project buys anonymously at retail, codes every vial and never accepts vendor samples or vendor certificates

Evidence verdict: Policy: describes the published Open Peptide Standard (Protocol v1.1). Why it is designed this way draws on published test-purchase studies. [1, 2, 3]

Last reviewed: Oct 27, 2026

In 30 seconds

A purchasing agent buys two matching vials from the same lot for the standard test panel (or three matching vials when destructive USP <71> sterility testing is ordered) through the seller's normal checkout, like any customer. Vendor samples and vendor certificates are never accepted. [1] [Policy]
Labels are replaced with a blind code before Vial A goes to an ISO/IEC 17025-accredited analytical lab for RP-HPLC purity, LC-MS identity, peptide content, and quantitative USP <85> bacterial endotoxin testing (which requires only a small portion from Vial A), so the lab does not know whose product it is testing. [1] [Policy]
Vial B stays sealed at −20 °C with a temperature logger for at least 12 months as the archive and referee vial, so a disputed result can be retested. When full destructive USP <71> membrane-filtration sterility testing is ordered, a third blind-coded vial (Vial C) from the same lot is required because the test consumes an entire sealed container, increasing both retail vial purchase and laboratory testing costs above the standard two-vial baseline. [1] [Policy]
Results publish within 7 days, pass or fail. Grades attach to the batch, not the seller, and at least 10% of batches are re-run at a second, unaffiliated lab. [1] [Policy]

Why buy blind at retail

A sample a seller chooses to send, or a certificate a seller provides, shows what the seller wants tested. A retail purchase shows what an ordinary buyer receives. Published test-purchase studies have found large gaps. Of 44 products sold online as SARMs (non-peptide "research chemicals"), only 52% contained a SARM, and the amount matched the label in only 41%. [2] [Lab, forensic] Semaglutide bought online without a prescription had purity far below its 99% label claim, and endotoxin was found in every sample. [3] [Observational] Of 13 SARM products bought online in Italy, 23% held a different SARM than labeled, 30% held undeclared drugs, and content ranged from 30% to 90% of the label claim. [4] [Lab, forensic]

Step 1: purchase

An independent purchasing agent buys 2 matching vials of the same lot for the standard analytical and endotoxin baseline (or 3 matching vials from the same lot when destructive USP <71> sterility testing is ordered) through normal checkout, with no disclosure that the purchase is for testing. Vendor-supplied samples and vendor certificates of analysis are never accepted as evidence. [1] [Policy]

Step 2: intake and blinding

On arrival, packaging, labels and lot numbers are photographed. The labels on each vial sent for testing are then removed or covered and replaced with a blind code. Each lab receives only the code and the test panel. [1] [Policy]

Step 3: testing and retained vials

The Standard gives each vial one role:

Vial A (blind-coded analytical and endotoxin vial) goes under a blind code to an ISO/IEC 17025-accredited analytical lab for the Standard's core and injectable panel: identity by LC-MS, purity by RP-HPLC, peptide content, and quantitative USP <85> kinetic LAL bacterial endotoxin testing (which requires only a small portion from Vial A). [1] [Policy]
Vial B (sealed −20 °C archive and referee vial) is kept unopened in a −20 °C archival freezer with a NIST-traceable temperature logger for at least 12 months. It is the archive and referee vial, held for retesting at a second, unaffiliated ISO/IEC 17025 lab if a result is disputed or selected for random referee verification. [1] [Policy]
Vial C (optional third blind-coded vial for destructive USP <71> sterility testing): because full USP <71> membrane-filtration sterility testing is destructive and consumes an entire sealed container, batches selected or underwritten for full USP <71> sterility require purchasing a 3rd matching vial from the same lot (shipped unopened under a blind code), which increases both retail vial acquisition and laboratory testing costs above the standard two-vial baseline. [1] [Policy]

Step 4: publication and grading

Results are published within 7 days of the lab report, whether the batch passes or fails. A grade applies to that batch and lot, never to the seller as a whole, because quality can change from lot to lot. [1] [Policy]

Step 5: referee testing and conflicts

At least 10% of batches are sent to a second, unaffiliated ISO/IEC 17025 referee lab, along with every disputed Fail and every batch with any related-party connection. The project takes no kickbacks or payments from sellers. [1] [Policy]

What blind testing cannot tell you

A result covers one lot, bought at one time. It cannot guarantee another lot, or a vial that was stored badly after purchase. It is a quality check, not a safety or effectiveness claim: a correctly made product still has only the evidence summarized on its compound page. [1] [Policy]

Evidence levels used on this page

[Regulatory] FDA, USP or WADA primary document or an FDA-approved label. [Controlled study] randomized trial or systematic review of trials. [Observational] surveillance, pharmacovigilance or cohort data. [Lab] analytical, cell or animal work. [Guidance] professional-society guidance. [Policy] Open Peptide Project published policy.

HPLC vs. LC-MS testing explained, What's really in the vial: net peptide content vs. label weight, Open Peptide Standard

References

Open Peptide Project. Testing standard (Open Peptide Standard, Protocol v1.1), read Oct 27, 2026. https://openpeptideproject.org/standard/
Van Wagoner RM, et al. Chemical composition and labeling of substances marketed as selective androgen receptor modulators and sold via the internet. JAMA. 2017. PMID 29183075.
Ashraf AR, et al. Multifactor quality and safety analysis of semaglutide products sold by online sellers without a prescription. J Med Internet Res. 2024. PMID 39509151.
Gaudiano MC, et al. Illegal products containing selective androgen receptor modulators purchased online from Italy. Sex Med. 2024. PMID 38560649.

Disclaimer: This page is for education only. It is not medical advice, and it does not endorse using, buying or preparing any unapproved product. Talk to a licensed clinician before you start, stop or change any treatment.