Matching a Certificate of Analysis to a Vial Label
Start with the physical item
A certificate of analysis may carry an impressive result yet still leave a basic question unanswered: does it describe the vial in front of you? Begin by recording the label exactly as received. Include the product name, stated amount, batch or lot code and any separate packaging identifier. Preserve leading zeros, punctuation and letter case rather than tidying them into a preferred format.
Photograph the label and keep the delivery record with it. A photograph provides a useful reference if a label later becomes damaged, but it does not establish chemical identity. The immediate aim is a readable record of what arrived at your UK laboratory.
Build the link between identifiers
Compare those observations with the certificate, including its material description and batch field. ICH Q7’s certificate section identifies batch numbers as certificate information. That guidance concerns pharmaceutical ingredients; it is a useful reference rather than evidence that a research supplier follows GMP.
Different codes need an explanation, not a guess. A supplier lot, manufacturer lot and laboratory sample number can legitimately coexist. Request a written mapping showing which identifier belongs to which organisation and how the particular delivered item connects to the tested sample. Similar product names alone cannot supply that missing link.
Keep uncertainty visible
A blank or redacted batch field limits what a public certificate can demonstrate. Record the gap and request a version or supporting statement that allows an authorised reviewer to verify the connection. Do not insert an inferred number into the original document. OECD’s data-integrity guidance provides a wider framework for preserving meaningful records.
For example, a certificate downloaded for a previous order should not automatically be assigned to a later delivery of the same named peptide. Keep both deliveries separate until their identifiers have been checked. Record who provided clarification and the date it was received.
Finish with a review decision
Use the COA library as a document starting point, then retain the exact file reviewed. Write a short conclusion: matched through stated identifiers, matched through a documented mapping, or unresolved. This is more informative than a folder simply labelled “passed”.
If the link remains unresolved, decide under your laboratory’s procedures whether additional documentation or testing is needed before the planned experiment. A matched certificate improves traceability; the reported tests still need separate assessment for relevance, method and limitations.
Related research reading
- What a Redacted Batch Field Means for Traceability
- Independent Testing Starts with the Sample That Was Sent
Explore the research blog and original batch-document library for further context.