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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Identity testing confirms the sample is the molecule named on the label. Without it, a purity number is floating free — pure what, exactly?
Purity is the share of the sample that's the target compound, with the rest being by-products, fragments, or filler. A higher number is better, but only once identity is confirmed.
Marketing loves a big purity figure because it sounds impressive in isolation. Always pair it with the identity result before you trust it.
Identity is not a checkbox; it is a measurement that matches a fingerprint. For a peptide the fingerprint is its mass. Mass spectrometry weighs the molecule and reports a molecular weight; that figure is compared with the theoretical weight calculated from the peptide's amino-acid sequence. A match within the instrument's tolerance (typically well under one dalton on a modern instrument) says the molecule in the vial has the composition the label claims. A miss says it does not, whatever the purity column reads.
The mass alone cannot distinguish two peptides with the same atoms in a different order, which is rare but possible. Laboratories that want to close that gap add a fragmentation step (MS/MS), which breaks the peptide into pieces and reads the pieces in order, or compare the sample's chromatographic retention time against a reference standard of the named compound. When a report lists a reference standard, it is telling you the identity check was made against a known-good sample rather than against arithmetic.
Purity almost always comes from HPLC: the sample is pushed through a column that separates components by how strongly they interact with it, and a detector draws a peak for each component as it emerges. The area under the main peak, divided by the area under all peaks, is the purity percentage. Two things follow. First, purity is a ratio of what the detector could see — components that do not absorb at the detector's wavelength are invisible to it and are neither counted as impurity nor as product. Second, the number depends on the method: a different column, gradient or wavelength can move it by a point or two on the same vial. That is why a report states the method next to the figure, and why comparing purity numbers across laboratories is less exact than comparing them within one.
The order of reading matters. Confirm identity first: is the molecular weight reported, and does it match the compound named on the label? Only then does the purity figure mean anything, because it is now a percentage of the right thing. A report that gives purity without identity is describing how clean an unknown is. A report that gives identity without purity is telling you the right molecule is present in an unstated amount. Neither is a complete answer, and a buyer who has read both columns is harder to impress with a single large number.
Identity and purity say nothing about quantity. A vial labelled 5 mg that contains 3 mg of a 99% pure, correctly identified peptide will pass both checks. Quantity is a separate assay (often a UV-absorbance or amino-acid analysis), and it appears on a report only when the client asked for it. The same is true of endotoxin and sterility, which are separate tests again. A COA answers the questions that were put to the laboratory; the useful habit is to notice which questions were not.
Related: HPLC vs mass spec · how to read a COA.
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244 published lab reports. 133 distinct products covered. 99.03% average purity across the 181 reports that state one, spanning 93.844% to 99.99%. Every one of them is hosted by Janoshik Analytical rather than by the seller, which is what makes the figures checkable instead of quotable. Shipping is domestic Canadian, pricing CAD, and the vendor has answered in public threads since November 2021. Itemised here.