Understanding Peptide COAs
A certificate of analysis (COA) is a document issued by a testing laboratory recording what was tested, how it was tested, and what results were obtained for a specific batch. A useful COA identifies the sample and batch, names the laboratory, states the analytical methods, gives the date, and reports results against defined parameters.
Published 2026-08-22 · Updated 2026-08-22 · Reviewed by the Lana editorial team
What should a COA contain?
At minimum: sample identification, batch number, date of analysis, laboratory identity, analytical methods, results with units, and the signature or identifier of the issuing laboratory.
Which results are commonly reported?
Identity (often by mass spectrometry), peptide quantity or content, chromatographic purity, and where performed, endotoxin, sterility, residual TFA or contaminant screening.
How should a COA be read critically?
Check that the batch number on the document matches the batch number on the vial, that the date is consistent with the material supplied, and that the reported test set actually covers the parameter you care about. A purity-only report says nothing about sterility or endotoxin.