Our quality commitment
At Lab Peptides France, quality is not an option but a fundamental requirement. We pay an independent laboratory for our own testing, and we publish the reports in full.
No unverifiable promises: every Janoshik report carries a verification key. Enter it on janoshik.com and the laboratory confirms the document itself, without going through us.
Our specification: ≥98% HPLC purity. Measured by Janoshik on five Retatrutide dosages and on our GHK-Cu 50 mg: 99.4 to 99.9%.
Quality control process
Our quality chain comprises several independent verification stages:
Synthesis in a specialized laboratory
Our peptides are produced by partner laboratories specialized in peptide synthesis. Solid-Phase Peptide Synthesis (SPPS) ensures maximum precision in amino acid sequencing.
HPLC Analysis (Chromatography)
High-Performance Liquid Chromatography (HPLC) precisely determines the purity percentage of the peptide. This method separates the sample components and quantifies the proportion of the target peptide relative to any impurities.
Mass Spectrometry (MS)
Mass spectrometry confirms the molecular identity of the peptide by measuring its exact mass. This technique verifies that the amino acid sequence matches the expected structure.
Third-party laboratory verification
For complete transparency, our testing is ordered and paid for by us at Janoshik, an independent laboratory. Our Retatrutide was tested blind: the laboratory did not know what it was analyzing. Every report carries a key you can check on janoshik.com, without going through us.
Verify a report on janoshik.comCertificate of Analysis (COA)
Whenever a reference has been tested, its product page publishes its Certificate of Analysis (COA): the document that gives the results measured by the laboratory.
What does a COA contain?
- Verification key : Identifier to enter on the laboratory website, which confirms the report without going through us.
- HPLC Purity : Purity percentage measured by chromatography, expressed as a percentage (e.g., 99.2%).
- Molecular Weight : Theoretical vs. observed molecular weight, confirming peptide identity.
- Appearance : Visual description of the product (white lyophilized powder, etc.).
- Analysis Date : Date on which the tests were performed.
- Storage Conditions : Storage recommendations.
Access to COAs
Whenever a COA exists, it is published directly on the product page, to view or download. Our Janoshik analyses carry a verification key: enter it on janoshik.com and the laboratory confirms the report itself, without going through us.
View the catalogStorage and handling
Peptide quality also depends on proper storage. Here are our recommendations for maintaining the integrity of your reagents:
Lyophilized peptide
Store at -20°C (freezer)
Stability: 2-3 yearsReconstituted peptide
Store at 2-8°C (refrigerator)
Stability: 14-30 daysLight protection
Keep away from direct light
Avoid UV and sunlightHumidity
Protect from moisture
Airtight vialFrequently asked questions
What does 98% purity mean?
A purity of 98% means that 98% of the sample consists of the target peptide, with the remaining 2% being minor impurities (synthesis residues, truncated peptides). This purity level is the standard for research-grade peptides.
How can I verify the authenticity of a COA?
Start with the verification key: our Janoshik reports carry one, to be entered on janoshik.com so the laboratory confirms the document itself. The certificate names the laboratory, the method used (HPLC and mass spectrometry), the measured purity and the net peptide content. Any doubt about a certificate, write to us.
What is the difference between HPLC and MS?
HPLC (chromatography) measures purity by separating sample components. Mass Spectrometry (MS) confirms the identity of the peptide by measuring its exact molecular mass. The two methods are complementary.
Are the peptides tested for endotoxins?
Not systematically. Our Janoshik analyses cover purity (HPLC) and the actual vial content; an endotoxin test (LAL) is a separate analysis, which we only display when it has been done. What is not on the certificate has not been measured.
How long can I store a lyophilized peptide?
A properly stored lyophilized peptide kept at -20°C and protected from light can remain stable for 2 to 3 years. Once reconstituted, it should be used within 14 to 30 days depending on the peptide.