CoA
Certificate of Analysis — a document from a third-party laboratory confirming the identity, purity, and potency of a research compound.
A CoA is the primary quality verification tool for research peptides. Reputable suppliers provide third-party CoAs — meaning an independent lab (not the vendor) tested the product — showing the compound matches its label claim in identity and purity. Key data points include HPLC purity percentage, mass spectrometry confirmation of the correct molecular weight, and absence of contaminants.
When evaluating a peptide vendor, always look for third-party CoAs with batch-specific results. Generic or vendor-issued CoAs without third-party lab names are insufficient. CoA dates should be recent and traceable to the specific batch you’re purchasing.