Lab Testing
Lab Testing
Every batch. Independently tested. UK laboratories.
When you order from Key Peptides, you receive a research compound that has been independently tested for purity and verified for identity by a UK laboratory. Every batch. No exceptions.
Why testing matters
In the research peptide market, the difference between suppliers comes down to one question: can they prove what's in the vial?
We can. And we publish the proof.
Every research compound we supply is tested before it reaches you. Each batch is analysed by an independent UK laboratory using two complementary methods: high-performance liquid chromatography (HPLC) for purity and quantitation, and mass spectrometry (MS) for confirmation of peptide identity. Together these methods answer two questions every researcher needs answered before they begin work:
- Is it the right compound?
- How pure is it?
The Certificate of Analysis included with every product gives you the documented answer to both.
Our testing process
Step 1 — Sourcing verification
Every compound is sourced from a verified manufacturer with documented quality control history. We do not work with unverified suppliers. Manufacturing-stage documentation accompanies every batch as it arrives.
Step 2 — Independent UK lab analysis
On receipt, samples from every batch are sent to our independent UK testing partner. Two analytical methods are performed:
- HPLC purity analysis — the sample is separated chromatographically and quantified to determine the percentage of the target peptide relative to impurities. Our specification is ≥98% purity for all research compounds.
- Mass spectrometry identity confirmation — the molecular mass of the peptide is measured and compared against the theoretical mass calculated from the amino acid sequence. A match confirms that the compound is what the manufacturer has stated it is.
Step 3 — Certificate of Analysis generation
Each batch receives its own Certificate of Analysis with the full analytical data. This is the document that accompanies your product. It is your record of what was tested, what was found, and when.
Step 4 — Batch traceability
Every product carries a batch number that links directly to the Certificate of Analysis for that batch. You can verify your specific batch at any time by referencing the batch number on the product page.
What HPLC tells you
HPLC (high-performance liquid chromatography) is the industry-standard method for analysing peptide purity. The technique separates the components of a sample by passing it through a chromatographic column under high pressure. Each component emerges from the column at a characteristic time and produces a peak on the resulting chromatogram. The size of each peak corresponds to the quantity of that component.
For your research peptide, the chromatogram shows the target peptide as the major peak and any impurities as minor peaks. The purity percentage is calculated as the area of the target peak divided by the total area of all peaks.
A purity of ≥98% — our standard specification — means at least 98% of the material in the vial is the target peptide.
What mass spectrometry tells you
Mass spectrometry (MS) measures the molecular mass of the peptide with high precision. Each peptide has a unique theoretical mass calculated from its amino acid sequence. If the measured mass matches the theoretical mass, the identity is confirmed.
This is what answers "is it the right compound?" — a confirmation that the peptide has the expected sequence and structure.
Sample Certificate of Analysis
Each Certificate of Analysis includes:
- Batch number and expiry
- Compound name and sequence
- Molecular formula and theoretical mass
- HPLC purity (with chromatogram)
- Mass spectrometry data (with mass spec trace)
- Peptide content and water content
- Manufacturing and testing dates
- Analytical methodology
Verifying your batch
The batch number on your product corresponds directly to the Certificate of Analysis for that batch. You can:
- View the COA on the relevant product page
- Request a copy of the COA for your specific batch by email
- Reference the batch number in any future correspondence
Frequently asked questions about testing
Why do you test in the UK?
Independent UK testing means the analysis is performed by laboratories operating under UK accreditation standards, with traceable methodology and documented chain of custody. This is different from suppliers who rely solely on manufacturer-supplied documentation.
Do you test every batch?
Yes. Every batch is tested independently before it is supplied. We do not rely on manufacturer-supplied documentation alone.
What if a batch fails testing?
Batches that do not meet our purity specification or fail identity confirmation are not supplied. They are returned to the manufacturer or destroyed, and a new batch is sourced.
Can I request additional testing?
We supply standard HPLC and MS analysis with every batch. For larger institutional orders or specific research applications requiring additional analytical methods, please contact us to discuss.
Backed by data. Available to verify. Always.
Browse our research compound collections, each with batch-specific Certificate of Analysis documentation included.
The research compounds described on this website are supplied strictly for laboratory and research purposes only. They are not licensed medicines and are not intended for human or veterinary use, administration, consumption, medical treatment, diagnosis, or therapeutic application. See our full Disclaimer.