Last week we got our first three independent test reports back from Janoshik Analytical. The results are now publicly available — and you can verify every number yourself.
Here is why we chose to invest in independent third-party testing, what the reports showed, and what it means for researchers ordering from us.
The Problem with In-House Testing
Every peptide supplier claims “third-party tested” or “HPLC verified.” But when you ask for the certificate, what you usually get is a document the vendor generated themselves. There is no way to independently verify that the test was actually performed, that the batch number matches, or that the purity number was not edited in Photoshop.
We run HPLC and mass spectrometry on every batch before it ships. We stand behind those results. But we also recognize that asking you to trust our own testing is asking a lot — especially when you are evaluating a new supplier.
This is a systemic problem in the research peptide industry. A 2023 study published in JAMA Network Open (Cohen et al.; PMID: 37594764) tested 57 peptide samples purchased as research chemicals and found that only 52% contained the labeled amount within 10% accuracy. Some samples contained no detectable peptide at all. The study concluded that independent analytical verification is essential for researchers who need reliable experimental materials.
That finding is consistent with what the research community has known anecdotally for years: in-house COAs from peptide suppliers are only as trustworthy as the supplier issuing them. Without independent verification, there is no way to distinguish a legitimate certificate from a fabricated one.
Why Janoshik?
Janoshik Analytical has been the go-to independent peptide testing lab in the research community for over a decade. Their public verification portal gets 100,000+ monthly visitors from researchers vetting suppliers. Every report includes a QR code that invalidates if the document is altered — meaning you cannot fake a Janoshik certificate.
We chose them because we wanted our customers to be able to verify our claims without taking our word for it. The reports live on Janoshik’s website, not ours. We have zero control over what they find or what they publish.
Several features make Janoshik’s testing particularly credible for the research community:
- Blind sample testing: Samples are submitted with product identifiers only — the lab does not know the supplier’s identity or claimed purity before running the analysis.
- Public verification portal: Every report gets a unique URL on verify.janoshik.com. Anyone can check the report without contacting us.
- Tamper-proof QR codes: The QR code on each report links to the original data. If even one character of the report is altered, the QR code no longer validates.
- Standardized methodology: HPLC analysis uses consistent column types, mobile phases, and gradient conditions across all peptide tests, making results comparable between suppliers.
Understanding the Testing Methods
For researchers evaluating COAs — whether ours or anyone else’s — it helps to understand what each test actually measures and what it does not.
HPLC Purity (High-Performance Liquid Chromatography): This is the primary quality metric for research peptides. HPLC separates the sample into its components based on their interaction with a stationary phase and a mobile phase gradient. The purity percentage represents the area of the target peptide peak relative to the total integrated peak area. A result of 99.766% means that 99.766% of the UV-absorbing material in the sample is the target peptide — the remaining 0.234% consists of synthesis-related impurities (deletion sequences, oxidized forms, deprotection byproducts).
What HPLC does not tell you: peptide content (how much of the total lyophilized mass is active peptide versus counterions and water), identity confirmation (HPLC alone cannot distinguish between peptides of similar hydrophobicity), or the presence of non-UV-absorbing contaminants.
Mass Spectrometry (MS): Confirms molecular identity by measuring the exact molecular weight of the peptide. For a correctly synthesized peptide, the observed mass should match the theoretical mass within instrument tolerance (typically +/- 1 Da for electrospray ionization). Mass spec catches problems that HPLC can miss — such as amino acid substitutions that happen to elute at the same retention time as the target peptide.
Gravimetric Analysis (Sample Weight): Measures the actual mass of lyophilized peptide in the vial. This is compared against the labeled fill weight. Slight overfill (like the Selank result at 11.56 mg on a 10 mg label) is common and acceptable — it provides a margin for powder loss during reconstitution. Significant underfill (like the Epitalon result at 45.31 mg on a 50 mg label) indicates a fill accuracy issue that needs to be addressed with the manufacturer.
What They Found
We sent three products from our current inventory for blind testing:
| Product | Labeled | Actual Weight | HPLC Purity | Report |
|---|---|---|---|---|
| Ipamorelin | 10mg | 10.02mg | 99.766% | View Report |
| Selank | 10mg | 11.56mg | 99.788% | View Report |
| Epitalon | 50mg | 45.31mg | 98.005% | View Report |
Two products came back above 99.7% purity with accurate or overfilled weights. The Epitalon result at 98.005% is below our stated threshold — we are addressing this with our supplier for the next batch.
We are publishing the Epitalon result exactly as Janoshik reported it. Transparency means showing every number, not just the flattering ones.
What the numbers mean in context
For researchers evaluating these results against the broader market:
- Ipamorelin at 99.766%: Exceeds the ≥98% threshold commonly cited as research-grade. The 10.02 mg fill weight is within 0.2% of the labeled amount — well within acceptable manufacturing tolerance for lyophilized peptides.
- Selank at 99.788%: The highest purity of the three samples. The 11.56 mg overfill (15.6% above label) means researchers get more active peptide per vial. Overfill is a deliberate manufacturing practice to ensure the labeled amount is always available after accounting for powder adherence to vial walls during reconstitution.
- Epitalon at 98.005%: Below our internal ≥99% standard but still above the 98% research-grade threshold. The ~2% impurity content could include truncated sequences (des-Ala or des-Glu variants) and oxidized methionine. The 45.31 mg fill (9.4% below label) is a fill accuracy issue we are correcting with our manufacturer. We are not pulling current Epitalon inventory from sale — the purity is research-grade — but we are holding the supplier to tighter fill specifications going forward.
How to Read a Peptide COA
Whether you are evaluating CertaPeptides or any other supplier, knowing how to critically read a Certificate of Analysis protects your research investment. Here is what to check:
- Purity method: Look for “RP-HPLC” (reverse-phase HPLC). Some COAs report “TLC purity” (thin-layer chromatography), which is a less precise method unsuitable for quantitative peptide analysis.
- Molecular weight confirmation: The COA should include an MS result confirming the expected molecular weight. Without this, you have no identity verification — just a purity percentage for an unidentified substance.
- Batch number: Every COA should reference a specific batch. If you order the same product twice and receive COAs with identical batch numbers but different order dates, that is a red flag — the supplier may be recycling a single COA across multiple batches.
- Appearance and solubility: Basic physical characterization confirms the product was actually tested. A COA that lists only purity without appearance, solubility, or other physical properties may be template-generated rather than batch-specific.
- Counterion: Check whether the peptide is supplied as TFA salt, acetate salt, or free base. This affects the net peptide content and can matter for sensitive assays.
- Independent verification: The most credible COAs come from or are verifiable through independent labs like Janoshik. A certificate you can cross-reference against a public database is fundamentally more trustworthy than one you cannot.
How to verify these results yourself
Every Janoshik report includes a unique verification code. Here is how to check:
- Click any “View Report” link above — it opens on Janoshik’s website, not ours
- Scan the QR code on the report to verify it has not been modified
- Check the purity percentage, sample weight, and testing methodology
If a vendor removes or obscures the QR code on a Janoshik certificate, that is a red flag. Legitimate reports always include full verification markers.
Our Ongoing Testing Program
These three products are the start. We plan to send additional batches to Janoshik on an ongoing basis, prioritizing our highest-volume products. Every report will be published publicly — both on our verification page and on Janoshik’s public portal.
We have also applied for Janoshik’s Distinctive Branding program, which adds our logo to all reports on their public listings page, and Premium Top Page placement for maximum visibility.
Our testing priority list for upcoming batches includes:
- BPC-157 and TB-500 — our highest-volume research peptides
- Semaglutide and tirzepatide — incretin peptides where purity verification is particularly important given the Cohen et al. (2023) findings
- GHK-Cu — copper peptide where metal chelation accuracy affects biological activity
If you want to see specific products tested next, let us know. We are building this verification program based on what matters to researchers.
Why Transparency Matters for Research Peptides
The research peptide market operates with minimal regulatory oversight compared to pharmaceutical-grade compounds. This creates an information asymmetry: suppliers know exactly what is in their products, but buyers have to take that information on trust. Independent testing inverts that dynamic — it gives researchers access to the same analytical data that suppliers have, verified by a neutral third party.
We publish every Janoshik result, including the ones that fall short of our internal standards, because selective transparency is not transparency. If we only published flattering results, the exercise would be no more trustworthy than self-issued COAs. The Epitalon result demonstrates this principle: a 98% purity with underfill is not the number we wanted to publish, but it is the number Janoshik found, and publishing it is the only way to make the testing program credible.
For researchers evaluating any peptide supplier — including us — independent verification is the single most reliable quality signal available. We encourage you to check our Janoshik reports, compare them against other suppliers’ results on the same portal, and make sourcing decisions based on verifiable data rather than marketing claims.
References
- Cohen PA, et al. (2023). Quantity of Semaglutide, Tirzepatide, and Retatrutide in Products Sold as Research Chemicals. JAMA Network Open. 2023;6(8):e2330490. PMID: 37594764. — This study tested 57 research peptide samples and found significant purity and dosing discrepancies, highlighting the importance of independent third-party verification.
- Sikiric P, Seiwerth S, Rucman R, Turkovic B, et al. (2011). Stable gastric pentadecapeptide BPC 157: novel therapy in gastrointestinal tract. Current Pharmaceutical Design, 17(16), 1612-1632. PMID: 21548867.
- Pickart L, Vasquez-Soltero JM, Margolina A. (2015). GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. BioMed Research International, 2015, 648108. PMID: 26236730.
All products mentioned are intended for research purposes only.