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Independent third-party testing by PeptideVerify: HPLC purity and LC-MS identity reports prepared for British Peptide Labs.
Independent third-party testing by PeptideVerify
PeptideVerify (Verify Analytik Ltd) is an independent third-party testing service. It analyses our compounds with two complementary methods and prepares each report for British Peptide Labs, so every certificate in this library is issued to us and published exactly as issued.
HPLC (high-performance liquid chromatography) separates the sample into its components and measures purity as the share of the main peak. LC-MS (liquid chromatography–mass spectrometry) measures molecular mass, which confirms the compound's identity.
A report from a separate testing service gives you a second record of the compound, made independently of us, that you can file with your laboratory notes and cite when you write up your results.
The method, step by step
- Step 1SampleA sample of the compound is received and logged by PeptideVerify, which assigns it the report number it carries from then on.
- Step 2HPLC purityReversed-phase HPLC with photodiode-array detection separates the sample and measures the main-peak share of the total peak area.
- Step 3LC-MS identityMass spectrometry measures the molecular mass and checks it against the expected value for the compound.
- Step 4ReportThe results are issued to British Peptide Labs as a numbered PeptideVerify report, published here as a PDF.
GLP-3 certificate of analysis: PeptideVerify report PV-82D8C6-XTFK
- Issued to
- British Peptide Labs
- Issuer
- PeptideVerify (Verify Analytik Ltd)
- Report ID
- PV-82D8C6-XTFK
- Issued
- 6 August 2026
- Methods
- HPLC-PDA and LC-MS
- Purity
- ≥99% (HPLC)
- Expected mass
- 4731.4 g/mol
Report PV-82D8C6-XTFK covers a GLP-3 sample analysed by PeptideVerify with two methods. The HPLC trace separates the sample on a reversed-phase column and records each component as a peak at 215 nm. The main peak is GLP-3, and its share of the total peak area is the purity measurement. The photodiode-array detector also records a UV spectrum across the peak, a check that it is a single species.
The LC-MS section confirms identity. Electrospray turns the lipidated peptide into a series of multiply charged ions, which are deconvoluted to one neutral mass and checked against the expected molecular weight from its formula, C221H342N46O68: 4731.4 g/mol. A match shows that the main peak is the full conjugate, peptide chain and lipid group together, because a missing residue or an incomplete lipid group would move the mass well outside the tolerance of the measurement.
The full PDF is published exactly as issued, and the GLP-3 product page lists the same formula, C221H342N46O68, and molecular weight beside its vial sizes and price.
Semaglutide certificate of analysis: PeptideVerify report PV-A459AC-BBHW
- Issued to
- British Peptide Labs
- Issuer
- PeptideVerify (Verify Analytik Ltd)
- Report ID
- PV-A459AC-BBHW
- Issued
- 19 August 2026
- Methods
- HPLC-PDA and LC-MS
- Purity
- ≥99% (HPLC)
- Expected mass
- 4113.58 g/mol
Report PV-A459AC-BBHW covers a Semaglutide sample analysed by PeptideVerify by HPLC-PDA and LC-MS. On the reversed-phase HPLC trace, recorded at 215 nm, the main peak is semaglutide: its share of the total peak area is the purity measurement, and the photodiode-array spectrum across the peak checks that it is a single species. The C18 diacid on the lysine side chain at position 20 makes the molecule strongly retained, so the main peak elutes late in the gradient.
The LC-MS section confirms identity. Electrospray produces a series of multiply charged ions, deconvoluted to one neutral mass and checked against the expected molecular weight from the formula C187H291N45O59: 4113.58 g/mol. A match confirms the full structure, including the Aib residue at position 2 and the lipid side chain with its linker, each of which sets the mass. A chain missing a residue, or one without its side chain, would read well away from the expected value.
The full PDF is published exactly as issued, and the Semaglutide product page lists the same formula, C187H291N45O59, and molecular weight beside its vial sizes and price.
Reading a certificate
Each report names the issuing laboratory, the report number and issue date, the methods used and the results for the sample. Read the chromatogram first: one dominant main peak, with any minor peaks small beside it. Then check the mass: the measured value should sit close to the expected molecular weight on the product page. Our guides walk through every section.
Frequently asked questions
PeptideVerify (Verify Analytik Ltd), an independent third-party testing service. Its reports are prepared for British Peptide Labs and published in this library.
HPLC measures purity as the share of the main peak in the chromatogram. LC-MS measures molecular mass, which confirms the compound's identity.
Every research compound has a purity of ≥99% (HPLC), stated on its product page.
Yes. Email your order number to info@britishpeptidelabs.com and we'll send the batch certificate for your order.
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