Certificate of analysis (revision 14)
Old revision·11:03, 27 Dec 2024·StyleSheetSybil
| Certificate of analysisQuality document | |
|---|---|
A certificate reports what was measured, on what, by what method, and by whom. Fields beyond those four are optional and frequently absent. | |
| Identification | |
| Abbreviation | CoA, COA |
| Issued by | The supplier, manufacturer or repackager |
| Scope | One named lot |
| Topic infobox · conventions | |
A certificate of analysis is a document issued with a consignment of material, reporting the results of specified tests carried out on a specified lot. In regulated pharmaceutical supply it is the record by which a quality unit releases material against a written specification, and it is retained as part of the batch record.[1] Outside that framework — which is where all material labelled for research use only sits — no obligation to issue one exists, no format is prescribed, and no authority audits what is written on it.
The document's evidential standing follows from who issues it. A certificate is a claim by its issuer about material it is selling. That is not a criticism: a claim made in writing, against a named lot, by an identifiable party, is a substantially stronger thing than no claim at all, and it is checkable in ways a verbal assurance is not. It is simply not the same as an independent measurement, and the two are frequently conflated.[2]
This article describes what the document normally contains, which fields carry information and which are decorative, how a certificate relates to an independently obtained result, and what a purchaser can reasonably ask for beyond it.
Fields and what each establishes
[edit]A certificate that is useful for anything carries at least seven fields. Each of them answers a question that cannot be answered from any of the others.
| Field | Answers | Comment |
|---|---|---|
| Product identity | What the material is claimed to be | Should give a name a reader can look up, not a catalogue code alone |
| Lot identifier | Which material this document describes | Must match the vial label; see Lot traceability |
| Test performed | What was measured | "Purity" alone is not a test; a method makes it one |
| Method | How it was measured | Without this, two results cannot be compared |
| Specification | What the result was measured against | A result with no specification is a number, not a release decision |
| Result | What was found | Should carry its units and its significant figures honestly |
| Release date and signatory | When and by whom the lot was released | A signature records release, not verification |
A specification is a list of tests, the analytical procedures referenced by them, and the acceptance criteria applied to the results, so a figure reported with no specification against it has not been the subject of a release decision at all.[3]
The distinction in the last row is the one most often misread. A signed certificate establishes that somebody at the issuing organisation accepted responsibility for releasing that lot. It does not establish that the tests were performed by an accredited laboratory, that the signatory saw the raw data, or that the material in the purchaser's hand came from the lot named.[2]
The fields most often missing
[edit]Across the certificates described in reports reaching this wiki, four determinations are absent far more often than they are present, and their absence has the same consequence in each case: the purity figure cannot be converted into a statement about mass.[1]
- Water content. A lyophilised peptide routinely holds several per cent water. Determined by Karl Fischer titration or by loss on drying, which are not interchangeable.
- Peptide content. The mass fraction of the vial that is the peptide itself, as opposed to water, counterion and residual solvent.
- Counterion identity and content. Trifluoroacetate is the commonest and can account for a large fraction of the mass of a basic peptide.
- Endotoxin. Reported for a small minority of material; unlike purity, it speaks to the process rather than to the shelf life, because endotoxin does not decrease on storage.
References
- ^ a b United States Pharmacopeia, General Chapter <1503>, "Quality Attributes of Synthetic Peptide Drug Substances" (informational). USP–NF, current revision. Describes the determinations that together characterise a synthetic peptide, and why purity alone does not.
- ^ a b ISO/IEC 17025:2017, General requirements for the competence of testing and calibration laboratories. International Organization for Standardization. The standard against which a testing laboratory's competence is assessed; self-description is not assessment against it.
- ^ International Council for Harmonisation, Q6A: Specifications — Test Procedures and Acceptance Criteria for New Drug Substances and New Drug Products: Chemical Substances. Defines a specification as a list of tests, references to analytical procedures and acceptance criteria; a result reported without one is not a release decision.