Certificate of Analysis (COA)

A formal document issued by an independent analytical laboratory confirming the identity, purity, and physical characteristics of a specific peptide batch. A legitimate COA includes: peptide sequence confirmation by mass spectrometry (LCMS), HPLC purity percentage with chromatogram, water content by Karl Fischer titration, and optionally endotoxin testing. The batch lot number ties the COA to the specific production run. Essential quality assurance documentation when evaluating research peptide suppliers.