Weigh 100-500 ug of lyophilized peptide. Reconstitute in a compatible aqueous or acetonitrile buffer. See our peptide reconstitution and storage guide for solvent selection.
Inject onto a C18 column with a water/acetonitrile + 0.1% TFA gradient. Detect at 214 nm. See HPLC vs mass spec for method selection.
Purity % = target peak area / total peak area × 100. Learn how to read the resulting report in how to read a peptide COA.
Run LC-MS or ESI-MS and match observed mass to the theoretical monoisotopic mass. Details: molecular analysis.
Add Karl Fischer moisture, LAL endotoxin, and heavy metal / residual solvent screening as required.
A complete COA includes chromatograms, mass spectra, calculated purity, impurity table, and pass/fail against specification. See third-party verification.
Purity quantification at 214 nm, 0.1% detection.
Matches observed mass to theoretical monoisotopic mass.
Validated methods, defensible data, audit-ready COA.
Ship your sample to our independent peptide testing lab. Full COA in 9-11 business days.