Lyophilisation: difference between revisions
Diff·revision 27 → 28·20:05, 22 Oct 2025
Difference between revision 27 and revision 28 of Lyophilisation. 2 lines changed; the page grew by 32 bytes.
| Revision 27 — 04:54, 1 Oct 2025 CategoryBot (talk) bot: sort category members 28,089 bytes +506 | Revision 28 — 20:05, 22 Oct 2025 SupplyWatchSuri (talk) add the figure for the lyophilisation cycle and caption it 28,121 bytes +32 | ||
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| 161 | The evidence available for any particular unregulated product is usually nil. A manufacturer's stability programme conducted under [[Cold chain|cold-chain]] and ICH conditions produces data that support a labelled storage statement; material distributed without such a programme carries a storage recommendation that is, at best, an inference from the behaviour of similar compounds.{{r|ich_q1a}} Community-collated observations of material that appeared to perform normally after warm transit exist but are self-reported, unblinded, and without pre-excursion analytical baselines, and cannot establish the absence of degradation.{{r|ppcommunity}} | 161 | The evidence available for any particular unregulated product is usually nil. A manufacturer's stability programme conducted under [[Cold chain|cold-chain]] and ICH conditions produces data that support a labelled storage statement; material distributed without such a programme carries a storage recommendation that is, at best, an inference from the behaviour of similar compounds.{{r|ich_q1a}} Community-collated observations of material that appeared to perform normally after warm transit exist but are self-reported, unblinded, and without pre-excursion analytical baselines, and cannot establish the absence of degradation.{{r|ppcommunity}} |
| 162 | 162 | ||
| + | 163 | {{main|Temperature excursion}} | |
| + | 164 | ||
| 163 | == Scale-up and transfer == | 165 | == Scale-up and transfer == |
| 164 | A cycle developed on a laboratory dryer frequently fails when transferred, and the reasons are well characterised. Radiative heat load differs between a small chamber with a glass door and a large chamber with cold walls, so the distribution of product temperatures differs. Condenser capacity and duct conductance limit the maximum sublimation rate a large dryer can sustain; when the rate approaches that limit, flow through the duct becomes choked and chamber pressure rises above its set point, warming every vial simultaneously. Shelf-temperature uniformity and the flatness of shelves both affect the vial heat transfer coefficient.{{r|rambhatla2003,tang2004}} | 166 | A cycle developed on a laboratory dryer frequently fails when transferred, and the reasons are well characterised. Radiative heat load differs between a small chamber with a glass door and a large chamber with cold walls, so the distribution of product temperatures differs. Condenser capacity and duct conductance limit the maximum sublimation rate a large dryer can sustain; when the rate approaches that limit, flow through the duct becomes choked and chamber pressure rises above its set point, warming every vial simultaneously. Shelf-temperature uniformity and the flatness of shelves both affect the vial heat transfer coefficient.{{r|rambhatla2003,tang2004}} |