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KPV testing in Canada

Three residues and 342 daltons. At this size the question is almost never identity — it is how much of what you weighed out is actually peptide.

$249CAD

Results in about five business days from arrival

Order this test
  • Identity by LC–MS/MS
  • Purity, with the method stated
  • Net peptide content in mg
  • Chromatographic peak data
  • Certificate anyone can verify

Three residues from a larger hormone

The C-terminal tripeptide of alpha-melanocyte-stimulating hormone: lysine, proline, valine. Trivially cheap to synthesise, which shapes where the risk sits.

Residues
3
Formula
C16H30N4O4
Mol. weight
342.4 Da
CAS
67727-97-3
Also called
alpha-MSH (11-13)

Small peptide, large counterion

The counterion is most of the difference

A trifluoroacetate counterion weighs 114 daltons. Against a peptide of 342, one counterion is a quarter of the combined mass before residual water is counted.

A vial can be genuine and high purity and still deliver far less peptide than the milligram figure implies. That is what net peptide content measures, and why we report it as its own number. The distinction in full.

Amidated versus free acid

KPV is sold both as the free acid and as the C-terminal amide, one dalton apart. They are different compounds. A label saying only KPV has not told you which.

Too cheap to counterfeit

There is little reason to substitute anything for a peptide this inexpensive, and considerable reason to underfill the vial.

What your certificate reports

  1. Identity — confirmed from precursor-to-product-ion transitions on a triple quadrupole instrument, not inferred from retention time.
  2. Purity — measured at the quantifying transition, with the method named on the report.
  3. Net peptide content — quantified against an external calibration curve and reported as its own figure, in milligrams. Why this is a different number from purity.
  4. Peak data — the chromatographic results behind each figure, printed on the certificate rather than held back.

Common questions

How much sample do you need?

One unopened vial. Detailed posting instructions arrive with your order confirmation, immediately after you pay.

Does it need to be shipped cold?

No. Lyophilised peptides travel safely at room temperature, which is how nearly all samples reach us.

Who actually performs the analysis?

An independent Ontario laboratory. Every certificate we issue names the facility that ran it — we are a testing service, not a laboratory, and we would rather say so than let you find out from the report.

What if the result comes back bad?

You get the result. We do not soften findings, and we do not charge differently depending on what the analysis shows.

Can I verify the certificate is genuine?

Yes. Every certificate carries an identifier that anyone can check against our records, including the vendor you bought from.

Related reading

ExplainedPurity is not contentA vial can be 99% pure and hold a quarter less peptide than the label says.Related testEpitalon testingSmaller still, with the same counterion problem.ExplainedHow labs know what is in a vialMass spectrometry without the jargon, and why weighing beats timing.

Test your kpv

$249 CAD · about five business days from arrival · never leaves Canada

Order this test