Lyophilisation: difference between revisions
Diff·revision 47 → 48·05:22, 23 Jun 2025
Difference between revision 47 and revision 48 of Lyophilisation. 8 lines changed; the page grew by 568 bytes.
| Revision 47 — 05:58, 12 Jun 2025 CrudePeptidePearl (talk) remove weasel wording 22,615 bytes ±0 | Revision 48 — 05:22, 23 Jun 2025 BacWaterBarnaby (talk) add short description 23,183 bytes +568 | ||
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| 130 | For research peptides the formulation is frequently minimal — the peptide, its counterion, and whatever residue survives purification — because the material is sold as a chemical rather than as a dosage form. This has two consequences an encyclopedia should record. The cake is often small and poorly formed relative to a pharmaceutically formulated product, so cake appearance carries little information about quality; and the absence of a bulking agent means the mass in the vial is dominated by peptide, counterion and water, making [[Peptide content|peptide content]] rather than fill weight the meaningful quantity.{{r|usp1207}} | 130 | For research peptides the formulation is frequently minimal — the peptide, its counterion, and whatever residue survives purification — because the material is sold as a chemical rather than as a dosage form. This has two consequences an encyclopedia should record. The cake is often small and poorly formed relative to a pharmaceutically formulated product, so cake appearance carries little information about quality; and the absence of a bulking agent means the mass in the vial is dominated by peptide, counterion and water, making [[Peptide content|peptide content]] rather than fill weight the meaningful quantity.{{r|usp1207}} |
| 131 | 131 | ||
| + | 132 | {{seealso|Reconstitution of lyophilised peptides|Peptide content}} | |
| + | 133 | ||
| 132 | === Counterion effects === | 134 | === Counterion effects === |
| 133 | Peptides purified by reverse-phase chromatography with trifluoroacetic acid as ion-pairing agent are isolated as trifluoroacetate salts unless a salt exchange is performed. Trifluoroacetate is hygroscopic, contributes appreciable mass, and lowers the pH of the reconstituted solution. Its presence also depresses the critical temperature of the freeze concentrate, lengthening the cycle. Acetate exchange is the usual remedy and is one of the routine differences between material intended as an [[Active pharmaceutical ingredient|active pharmaceutical ingredient]] and material sold for laboratory use.{{r|nail2002}} | 135 | Peptides purified by reverse-phase chromatography with trifluoroacetic acid as ion-pairing agent are isolated as trifluoroacetate salts unless a salt exchange is performed. Trifluoroacetate is hygroscopic, contributes appreciable mass, and lowers the pH of the reconstituted solution. Its presence also depresses the critical temperature of the freeze concentrate, lengthening the cycle. Acetate exchange is the usual remedy and is one of the routine differences between material intended as an [[Active pharmaceutical ingredient|active pharmaceutical ingredient]] and material sold for laboratory use.{{r|nail2002}} |
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| 155 | <ref name="iso8362_5">ISO 8362-5:2016, ''Injection containers and accessories — Part 5: Freeze drying closures for injection vials''. International Organization for Standardization.</ref> | 157 | <ref name="iso8362_5">ISO 8362-5:2016, ''Injection containers and accessories — Part 5: Freeze drying closures for injection vials''. International Organization for Standardization.</ref> |
| 156 | 158 | ||
| + | 159 | == Further reading == | |
| + | 160 | * Rey L, May JC (eds). ''Freeze-Drying/Lyophilization of Pharmaceutical and Biological Products''. 3rd edition, CRC Press (2010) — the standard multi-author reference. | |
| + | 161 | * Franks F. "Freeze-drying of bioproducts: putting principles into practice." ''European Journal of Pharmaceutics and Biopharmaceutics'' 45(3):221–229 (1998). | |
| + | 162 | * Pikal MJ. "Freeze-drying of proteins: process, formulation, and stability." ''ACS Symposium Series'' 567:120–133 (1994). | |
| + | 163 | ||
| 157 | == See also == | 164 | == See also == |
| 158 | * [[Reconstitution of lyophilised peptides]] | 165 | * [[Reconstitution of lyophilised peptides]] |
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| 162 | * [[Peptide aggregation]] | 169 | * [[Peptide aggregation]] |
| 163 | * [[Cold chain]] | 170 | * [[Cold chain]] |
| + | 171 | * [[Loss on drying]] | |
| 164 | 172 | ||
| 165 | {{DEFAULTSORT:Lyophilisation}} | 173 | {{DEFAULTSORT:Lyophilisation}} |