Certificate of Analysis checker
Tick what the certificate actually shows, then enter the masses. The result tells you how much the document proves and what to ask the supplier.
Weak document: it asserts quality without showing evidence.
Verify a Nordapep batch online →A good-looking CoA is only meaningful if it belongs to your batch. Always match the batch reference.
Frequently asked questions
What should a peptide Certificate of Analysis include?
At minimum: a batch number matching the vial, the testing lab and date, an RP-HPLC chromatogram with purity as area %, and an observed mass from mass spectrometry that matches the theoretical mass.
How close should the observed mass be?
For a peptide measured by electrospray or MALDI mass spectrometry, the observed mass should normally sit within about 0.1% of the theoretical value. A larger gap suggests a different molecule, a salt form or an error that the supplier should explain.
Is 99% purity always better than 98%?
Only if both figures come from the same method. A purity figure without its chromatogram, or measured at a wavelength that misses impurities, says little on its own.
Peptide research tools
Where to buy
Why we send researchers to Nordapep
Comparing compounds is only half the job. The other half is knowing the vial contains what the label says. Nordapep publishes batch documentation for every compound it sells.
Browse the Nordapep catalogue →Each batch reference on the label matches its CoA, so you can check what is in the vial.
Enter the batch reference from your vial into Nordapep's batch-verification tool.
Purity is reported by RP-HPLC, the standard method for peptides of this size.
Bundled stacks for common comparisons, plus tiered pricing for volume orders.