Counterfeit peptide: difference between revisions
Diff·revision 10 → 11·01:24, 7 Mar 2025
Difference between revision 10 and revision 11 of Counterfeit peptide. 5 lines changed; the page grew by 610 bytes.
| Revision 10 — 19:56, 23 Feb 2025 StubSorterBot (talk) bot: normalise citation format 2,733 bytes ±0 | Revision 11 — 01:24, 7 Mar 2025 ShortDescShai (talk) state the method the reporting service uses, since it is not the only one available 3,343 bytes +610 | ||
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| 20 | The confounding case is a peptide of similar mass in the same family. Analogues within the incretin class differ by hundreds of daltons and are readily distinguished; a deletion sequence of the intended peptide differs by a single residue and is a synthesis defect rather than a counterfeit, though the analytical challenge is comparable. See [[Analytical method validation]]. | 20 | The confounding case is a peptide of similar mass in the same family. Analogues within the incretin class differ by hundreds of daltons and are readily distinguished; a deletion sequence of the intended peptide differs by a single residue and is a synthesis defect rather than a counterfeit, though the analytical challenge is comparable. See [[Analytical method validation]]. |
| 21 | 21 | ||
| + | 22 | == Dilution with bulking agent == | |
| + | 23 | Dilution adds an undeclared excipient — mannitol and lactose are the ones most often reported — to a genuine peptide, so that a nominal quantity of solid contains less peptide than stated.{{r|reports}} | |
| + | 24 | ||
| + | 25 | Chromatographic purity does not detect it. A sugar does not absorb appreciably at 214 nm and will not appear in the chromatogram; the purity figure is computed over what was detected, and the bulking agent is not part of it. The determination that detects dilution is [[Peptide content|peptide content]], which measures the mass fraction of the solid that is peptide. | |
| + | 26 | ||
| 22 | == References == | 27 | == References == |
| 23 | {{reflist}} | 28 | {{reflist}} |