Peptide aggregation: difference between revisions
Diff·revision 11 → 12·09:54, 6 Feb 2025
Difference between revision 11 and revision 12 of Peptide aggregation. 11 lines changed; the page grew by 786 bytes.
| Revision 11 — 13:05, 18 Jan 2025 Chromatokid (talk) state that ultraviolet response is not uniform across impurities 3,115 bytes ±0 | Revision 12 — 09:54, 6 Feb 2025 LeanMassLars (talk) add the detection wavelength 3,901 bytes +786 | ||
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| 1 | {{Infobox concept | 1 | {{Infobox concept |
| 2 | | name = Peptide aggregation | 2 | | name = Peptide aggregation |
| + | 3 | | subtitle = Degradation route | |
| 3 | | image = peptide-chain.svg | 4 | | image = peptide-chain.svg |
| 4 | | Reversible form = Self-association into defined oligomers | 5 | | Reversible form = Self-association into defined oligomers |
| ⋮ | ⋮ | ||
| 19 | 20 | ||
| 20 | Interfacial aggregation is the mechanism most often encountered in handling. The air–liquid interface presents a hydrophobic surface at which peptides adsorb and unfold, so shaking a vial is substantially worse than swirling it. The same applies to repeated passage through a narrow needle.{{r|usp1503}} | 21 | Interfacial aggregation is the mechanism most often encountered in handling. The air–liquid interface presents a hydrophobic surface at which peptides adsorb and unfold, so shaking a vial is substantially worse than swirling it. The same applies to repeated passage through a narrow needle.{{r|usp1503}} |
| + | 22 | ||
| + | 23 | == Detection == | |
| + | 24 | | Method | Detects | Limitation | | |
| + | 25 | |---|---|---| | |
| + | 26 | | Visual inspection | Visible particles, haze | Insensitive to soluble oligomers | | |
| + | 27 | | Size-exclusion chromatography | Soluble aggregates | Dissociating conditions can hide reversible species | | |
| + | 28 | | Dynamic light scattering | Particle size distribution | Dominated by the largest particles present | | |
| + | 29 | | [[Reverse-phase HPLC]] | Little or nothing | Aggregates often dissociate on the column | | |
| + | 30 | ||
| + | 31 | The last row is the important one for reading certificates. A reverse-phase purity determination is run under denaturing conditions with organic solvent and acid; aggregates dissociate and are counted as monomer. A high purity figure by that method says nothing about aggregation state.{{r|usp1503}} | |
| 21 | 32 | ||
| 22 | == References == | 33 | == References == |