Preparative HPLC purification: difference between revisions
Diff·revision 7 → 8·15:50, 23 Oct 2024
Difference between revision 7 and revision 8 of Preparative HPLC purification. 6 lines changed; the page grew by 665 bytes.
| Revision 7 — 18:47, 3 Oct 2024 StubSorterBot (talk) bot: normalise unit spacing 2,696 bytes +388 | Revision 8 — 15:50, 23 Oct 2024 SPPS_Sorrel (talk) clarify that the cake appearance is an indicator, not a specification 3,361 bytes +665 | ||
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| 1 | {{Infobox method | 1 | {{Infobox method |
| 2 | | name = Preparative HPLC purification | 2 | | name = Preparative HPLC purification |
| + | 3 | | image = chromatogram.svg | |
| 3 | | Objective = Collect a fraction, not measure one | 4 | | Objective = Collect a fraction, not measure one |
| 4 | | Scale = Grams to kilograms per run | 5 | | Scale = Grams to kilograms per run |
| ⋮ | ⋮ | ||
| 18 | 19 | ||
| 19 | Fraction collection may be time-based or triggered by detector signal. Detector signals saturate at preparative loadings, so collection windows are often set by prior experiment rather than by real-time response, and a shift in retention between runs then costs yield or purity.{{r|usp621}} | 20 | Fraction collection may be time-based or triggered by detector signal. Detector signals saturate at preparative loadings, so collection windows are often set by prior experiment rather than by real-time response, and a shift in retention between runs then costs yield or purity.{{r|usp621}} |
| + | 21 | ||
| + | 22 | == What follows the column == | |
| + | 23 | Collected fractions are pooled, and the pooling decision determines the composition of the lot. A pool assembled from central fractions differs from one that includes edge fractions, and both may be described by the same product name.{{r|usp1503}} | |
| + | 24 | ||
| + | 25 | Solvent is removed and the peptide isolated, usually by [[Lyophilisation|lyophilisation]]. Because the mobile phase contains trifluoroacetic acid, the isolated solid is a [[Trifluoroacetate counterion|trifluoroacetate salt]] unless a salt-exchange step is performed, and the counterion contributes mass that is not peptide — see [[Peptide content]]. | |
| 20 | 26 | ||
| 21 | == References == | 27 | == References == |