Certificate of analysis: difference between revisions
Diff·revision 9 → 10·05:00, 5 Nov 2024
Difference between revision 9 and revision 10 of Certificate of analysis. 11 lines changed; the page grew by 1,237 bytes.
| Revision 9 — 09:41, 22 Oct 2024 PurityClaimPia (talk) ce per PP:MOS 4,248 bytes +389 | Revision 10 — 05:00, 5 Nov 2024 ForgeryFinder (talk) move a stray full stop inside the reference 5,485 bytes +1,237 | ||
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| 1 | {{Infobox concept | 1 | {{Infobox concept |
| 2 | | name = Certificate of analysis | 2 | | name = Certificate of analysis |
| + | 3 | | image = coa-sheet.svg | |
| + | 4 | | caption = A certificate reports what was measured, on what, by what method, and by whom. Fields beyond those four are optional and frequently absent. | |
| 3 | <!-- Identification --> | 5 | <!-- Identification --> |
| 4 | | Abbreviation = CoA, COA | 6 | | Abbreviation = CoA, COA |
| ⋮ | ⋮ | ||
| 30 | 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.{{r|iso17025}} | 32 | 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.{{r|iso17025}} |
| 31 | 33 | ||
| + | 34 | == The fields most often missing == | |
| + | 35 | 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.{{r|usp1503}} | |
| + | 36 | ||
| + | 37 | * '''Water content.''' A lyophilised peptide routinely holds several per cent water. Determined by [[Karl Fischer titration]] or by [[Loss on drying|loss on drying]], which are not interchangeable. | |
| + | 38 | * '''[[Peptide content|Peptide content]].''' The mass fraction of the vial that is the peptide itself, as opposed to water, counterion and residual solvent. | |
| + | 39 | * '''Counterion identity and content.''' Trifluoroacetate is the commonest and can account for a large fraction of the mass of a basic peptide. | |
| + | 40 | * '''[[Bacterial endotoxin test|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. | |
| + | 41 | ||
| 32 | == References == | 42 | == References == |
| 33 | {{reflist}} | 43 | {{reflist}} |
| ⋮ | ⋮ | ||
| 40 | [[Category:Testing methodology]] | 50 | [[Category:Testing methodology]] |
| 41 | [[Category:Traceability]] | 51 | [[Category:Traceability]] |
| + | 52 | [[Category:Quality and testing]] | |
| 42 | 53 |