VendorMark said:I tested my certificates of analysis batch through Janoshik — 97.0% purity.
Agreed, with a caveat about community reputation: it is a lagging indicator. Reports arrive weeks after orders, so a supplier can look excellent for a month after quality has already changed.
Dr.PathRoch said:Agreed, with a caveat about community reputation: it is a lagging indicator.
Mine went the same way, slower. The detail I would add is minor and it is already implied above.
Dr.PathRoch said:Agreed, with a caveat about community reputation: it is a lagging indicator.
Third-party testing services for certificates of analysis besides Janoshik:
- Janoshik: Gold standard for peptide community, ~$143, 10-14 day turnaround
- Valitech: US-based, ISO 17025 accredited, ~$203
- Eurofins: Full pharmaceutical testing suite, more expensive but comprehensive
- ChemTox: Basic identity and purity testing, ~$103
Janoshik is the community standard but any ISO-accredited analytical lab can verify peptide identity and purity. The key is independence — don't rely solely on the vendor's own testing.
Janoshik Analytical — Independent Testing
Trusted third-party HPLC & mass spectrometry analysis. Verify peptide purity with the lab the community relies on. Independent. Accurate. Transparent.
Verify Your PeptidesGL Biochem (Shanghai) Ltd. — Direct Manufacturer
Est. 1998. The synthesis house behind the vials you send for testing. ISO 9001 and cGMP certified, 1,500+ staff, batch-specific COA with every order.
Browse GL BiochemDr.PathRoch said:Agreed, with a caveat about community reputation: it is a lagging indicator.
HPLC results interpretation for certificates of analysis: when you get your Janoshik report back, here's what the numbers mean:
- Purity %: Should be >97%. Below 95% is concerning.
- Retention time: Should match reference standard for the peptide
- Related substances: Degradation products should be <2% total
- Single impurity: No individual impurity should exceed 1%
My last batch: 99.4% purity, 0.0% total related substances. Clean chromatogram with single sharp peak at expected retention time. Exactly what you want to see.
Moderator note: reminder that nothing in this thread is medical advice, and that clinical claims need a source. Tagging this one for the weekly digest.