Canadian research peptides · independently tested
Canada’s most documented peptide source — 244 independent lab reports, a published purity floor of 93.844%, and domestic shipping.
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Mass spectrometry weighs the molecule and matches it to the expected mass. It answers "is this the right compound?" — but on its own it says little about how much filler or by-product rides along.
HPLC separates a sample into its components and reports the percentage that is the target compound. It answers "how clean is it?" — but on its own it doesn't confirm the main peak is the right molecule.
A high HPLC purity number on the wrong molecule is meaningless, and a confirmed identity with unknown purity is half a picture. Read both, together.
High-performance liquid chromatography separates a mixture into its components. The dissolved sample is pumped at high pressure through a column packed with fine particles; different molecules cling to the packing with different strength and therefore leave the column at different times. A detector at the end — for peptides, usually ultraviolet absorbance at a wavelength the peptide bond absorbs — draws a trace of what comes out and when. Each component is a peak; the area under a peak is proportional to how much of that component was present. Purity is the main peak's area as a share of the total. What HPLC cannot do is tell you what any peak is. It knows that something came out at 12.4 minutes and how much; it does not know that the something is the peptide on the label.
Mass spectrometry weighs molecules. The sample is ionised, the ions are pushed through a field that sorts them by mass-to-charge ratio, and a detector records which masses arrived. For a peptide the result is a molecular weight, which is compared with the weight calculated from the sequence on the label. That is an identity test: the right molecule has the right mass, and a different molecule almost always does not. What mass spectrometry is poor at is quantity. Ionisation efficiency varies from molecule to molecule, so the size of a mass peak is not a reliable measure of how much of it was there; a report that quotes a purity figure “by MS” is usually reporting something looser than an HPLC purity.
Together the two instruments answer two different questions. HPLC says how clean the sample is; MS says what it is. A sample can be 99% clean and the wrong molecule, or the right molecule at 80% clean, and either instrument alone would miss one of those. This is why a complete peptide COA reads “identity confirmed by MS, purity by HPLC” and reports the method for each. The combined instrument, LC-MS, runs the chromatography and then weighs each peak as it emerges, so every peak in the purity trace gets an identity — which also answers the question HPLC alone leaves open: what were the impurities?
The method line tells you what was and was not measured. “HPLC-UV, 220 nm” is a purity measurement of everything that absorbs at that wavelength; salts and water do not, and are not counted. “MALDI-TOF” or “ESI-MS” is an identity measurement. “LC-MS” is both. A report that lists only one of these has answered only one of the two questions, and the missing one is worth asking about before treating the certificate as complete.
Neither HPLC nor MS reports how many milligrams are in the vial, whether the contents are sterile, or whether endotoxin is present. Those are separate assays. A high purity from HPLC and a matching mass from MS describe the material's composition, not its amount or its microbiological state, and a vendor's testing claim is only as broad as the assays that were actually run.
Related: purity vs identity on a COA · how to read a COA.
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Testing: 244 Janoshik reports across 133 products, 99.03% mean purity over the 181 that state a figure, 93.844% to 99.99%, each hosted on the testing lab's domain. Shipping: from inside Canada, in Canadian dollars, with no customs step for a Canadian buyer. Time: the vendor has been answering publicly in its own forum threads since November 2021. All of it, itemised.