Certificate of analysis: difference between revisions
Diff·revision 21 → 22·18:48, 28 Apr 2025
Difference between revision 21 and revision 22 of Certificate of analysis. 8 lines changed; the page grew by 583 bytes.
| Revision 21 — 10:29, 9 Apr 2025 PancreasPru (talk) state that the sample was not drawn blind, so it represents the vial and not the lot 7,513 bytes +541 | Revision 22 — 18:48, 28 Apr 2025 CategoryBot (talk) bot: update parent category chain 8,096 bytes +583 | ||
|---|---|---|---|
| 53 | Disagreement is equally easy to over-read. Two laboratories running different gradients on different column chemistries, integrating valley-to-valley rather than by drop-line, and calibrating against different [[Reference standard|reference standards]], will produce different numbers for the same vial and both may be honest. This is why the '''method''' field matters more than its position on the page suggests: without it, a comparison between a certificate and a report is a comparison between two unspecified procedures.{{r|usp1503}} | 53 | Disagreement is equally easy to over-read. Two laboratories running different gradients on different column chemistries, integrating valley-to-valley rather than by drop-line, and calibrating against different [[Reference standard|reference standards]], will produce different numbers for the same vial and both may be honest. This is why the '''method''' field matters more than its position on the page suggests: without it, a comparison between a certificate and a report is a comparison between two unspecified procedures.{{r|usp1503}} |
| 54 | 54 | ||
| + | 55 | === What to request beyond the certificate === | |
| + | 56 | A purchaser wanting a certificate figure to be comparable with an independently obtained one needs four further items, all of which exist in the issuer's records whether or not they appear on the document: | |
| + | 57 | ||
| + | 58 | # the gradient and column chemistry the determination was run on; | |
| + | 59 | # the detection wavelength, since ultraviolet response is not uniform across impurities; | |
| + | 60 | # the water determination, with the method that produced it; | |
| + | 61 | # the [[Peptide content|peptide content]], or the counterion identity and content from which it can be derived. | |
| + | 62 | ||
| 55 | == References == | 63 | == References == |
| 56 | {{reflist}} | 64 | {{reflist}} |