Thymalin — analytical characterisation
Chromatographic conditions, identity, related substances, presentation, reconstitution and in-use stability.
§6Analytical characterisation
§6.1Chromatographic conditions
- Column
- Size-exclusion chromatography to characterise the molecular-weight distribution, and reverse-phase to produce a fingerprint chromatogram — neither yields a purity figure
- Mobile phase and gradient
- Method-dependent
- Detection
- UV 214 nm and 280 nm for fingerprinting
- Retention
- Not applicable; the appropriate output is a comparison against a reference fingerprint, not a retention time
§6.2Identity by mass spectrometry
Mass spectrometry of an extract produces a complex spectrum that can serve as a fingerprint but cannot confirm an identity in the conventional sense.[3]
§6.3Related substances and degradation
Table 7. Related substances recorded for Thymalin, with the process or storage route that generates each and its analytical signature.
| Related substance | Origin | Analytical signature |
|---|---|---|
| The concept does not apply | Undefined composition | For an extract there is no distinction between product and impurity; the relevant controls are process consistency, fingerprint comparability, bioburden, endotoxin and adventitious-agent safety |
| Endotoxin | Animal tissue and processing | The bacterial endotoxin test is essential for any animal-derived injectable and is not reported in this supply channel |
| Adventitious agents | Bovine source | Requires documented sourcing from a controlled geography and a validated inactivation step |
Degradation routes
- Not characterisable
§7Presentation, reconstitution and storage
§7.1Presentation and reconstitution
- Presentation
- Lyophilised extract in vial
- Reconstitution
- The approved presentation is reconstituted with sodium chloride solution immediately before intramuscular injection.
- Storage, lyophilised
- 2–8 °C
- Storage, reconstituted
- Immediate use
- In-use period
- Immediate use
This monograph exists to mark a boundary. A defined synthetic peptide and an undefined animal extract are different kinds of thing, and applying the vocabulary of purity and identity to the second produces documents that appear rigorous while conveying nothing.
§7.2In-use stability
Applicable standards: CEI-MS-01 · CEI-MS-02 · CEI-MS-03 · CEI-MS-04 · CEI-MS-05 · CEI-MS-06. The full series is at methodological standards.
Working calculators: reconstitution and insulin-unit conversion · purity against peptide content · certificate minimum-data checker.
References cited on this page
References are numbered in order of first citation in this document. Each superscript in the text links to its entry below.
- United States Pharmacopeial Convention. General Chapter ⟨1225⟩ Validation of Compendial Procedures. United States Pharmacopeia — National Formulary (USP–NF) 2024;USP 2024 Issue 1. identifier not held by the Institute
- International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH Q2(R2) Validation of Analytical Procedures. ICH Harmonised Guideline 2023;Step 4 version, 1 November 2023. identifier not held by the Institute
- International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH Q6B Specifications: Test Procedures and Acceptance Criteria for Biotechnological/Biological Products. ICH Harmonised Tripartite Guideline 1999;Step 4 version. identifier not held by the Institute
- International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH Q1A(R2) Stability Testing of New Drug Substances and Products. ICH Harmonised Tripartite Guideline 2003;Step 4 version. identifier not held by the Institute
- Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharmaceutical Research 2010;27(4):544–575. doi:10.1007/s11095-009-0045-6 · PMID 20143256
Identifiers are reproduced only where the Institute holds them. Where a digital object identifier or PubMed identifier is not shown, the Institute has recorded the journal and year and has not constructed an identifier.