Purity, Testing & Certificates of Analysis
Every batch we supply is HPLC purity-tested and identity-confirmed by mass spectrometry before it reaches a South African lab. This page explains exactly what that means and what you can ask us for.
HPLC purity analysis
Every batch is analysed by high performance liquid chromatography. The chromatogram shows the target peak and any impurities, giving the numerical purity figure printed on the Certificate of Analysis.
Mass spectrometry identity
Purity alone does not prove identity. Mass spectrometry confirms that the measured molecular weight matches the theoretical value for the stated amino acid sequence.
Batch-linked Certificate of Analysis
Each COA is tied to a specific batch number, matching the number printed on your vial. A certificate that does not carry your batch number is not verification of your product.
Controlled cold storage
Lyophilised stock is held under controlled cold storage at our Johannesburg facility until dispatch, protecting seal integrity and preventing moisture ingress.
Sealed, discreet dispatch
Orders placed before 2 pm are dispatched the same day from Johannesburg by tracked courier, in sealed, discreetly packaged vials.
Research-use compliance
All compounds are supplied strictly for in-vitro laboratory research. They are not registered medicines and are not supplied for human or veterinary use.
How to read a Certificate of Analysis
A Certificate of Analysis is a batch document, not a marketing sheet. Three things on it matter: the batch number, the HPLC purity figure, and the mass spectrometry result confirming molecular weight.
Check that the batch number on the certificate matches the number printed on your vial. A generic certificate with no matching batch reference tells you nothing about the product in your hand — this is the single most common gap when buying research peptides online.
The HPLC purity figure is the percentage of the sample that eluted as the target peak. The mass spectrometry result should state a measured molecular weight within tolerance of the theoretical weight for the stated sequence.
Our peptide glossary defines each of these terms in full, and the storage and handling guide covers what happens to a verified batch after it arrives.
Frequently asked questions
- What purity are Peptides Lab research peptides?
- Our catalogue is supplied at 99% or higher purity by HPLC for the majority of compounds, with a minimum standard of 97% across the range. The exact figure for your batch is stated on its Certificate of Analysis.
- How do I get a Certificate of Analysis?
- Request the COA for your batch number by email or through the contact form and we will send the batch-specific document, which reports HPLC purity, mass spectrometry identity confirmation and appearance.
- What does HPLC verified mean?
- High performance liquid chromatography separates the sample into its components and measures the proportion that is the target peptide. A 99% HPLC result means 99% of the material eluted as the target peak.
- Why is mass spectrometry needed as well as HPLC?
- HPLC measures purity but not identity. Mass spectrometry confirms the molecular weight matches the theoretical value for the sequence, proving the compound is what the label says it is.
- Do peptides need cold-chain shipping in South Africa?
- Not in lyophilised form. Freeze-dried peptides are stable at ambient temperature for the duration of normal courier transit, which is why sealed research vials ship safely nationwide without cold chain.