Abstract
The stability of prothrombin and factor VII was studied using accelerated degradation tests in three preparations of freeze-dried pooled normal plasmas. In a previous report (Brozović, Gurd, Robertson, and Bangham, 1971) factor X was shown to be relatively unstable in these preparations of freeze-dried plasma: it was calculated that up to 8% of the original factor X activity would be lost after 10 years at −20°C, up to 54% at 4°C, and up to 90% at room temperature.
The losses of factor VII activity were estimated to be negligible at −20°C, between 2 and 18% at 4°C, and between 20 and 70% of the original activity at 20°C, after 10 years of storage. Prothrombin was found to be less stable than factor VII: the expected loss in 10 years at −20°C may be up to 4%, at 4°C up to 30%, and at 20°C up to 83% of the initial activity. These findings indicate that in freeze-dried plasma prothrombin as well as factor X may be insufficiently stable for plasma to serve as long-term reference material for the standardization of the one-stage prothrombin time. Moreover, the loss of prothrombin and factor X in freeze-dried plasma stored at 4°C may be so high that when it is required to preserve these factors it may be necessary to store freeze-dried plasma at lower temperatures.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Alderson M. R., Poller L., Thomson J. M. Validity of the British system for anticoagulant control using the national reagent. J Clin Pathol. 1970 May;23(4):281–285. doi: 10.1136/jcp.23.4.281. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bangham D. R., Robertson I., Gurd L. J., Brozović M. Factor X in freeze-dried factor- VIII reference plasma. Br J Haematol. 1971 Aug;21(2):201–208. doi: 10.1111/j.1365-2141.1971.tb03430.x. [DOI] [PubMed] [Google Scholar]
- Biggs R., Bangham D. R. Standardization of the one-stage prothrombin time test for the control of anticoagulant therapy: availability and use of thromboplastin reference preparations. Br Med J. 1971 Aug;3(5772):470–471. doi: 10.1136/bmj.3.5772.470. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Biggs R., Denson K. W. Standardization of the one-stage prothrombin time for the control of anticoagulant therapy. Br Med J. 1967 Jan 14;1(5532):84–88. doi: 10.1136/bmj.1.5532.84. [DOI] [PMC free article] [PubMed] [Google Scholar]
- JERNE N. K., PERRY W. L. The stability of biological standards. Bull World Health Organ. 1956;14(1):167–182. [PMC free article] [PubMed] [Google Scholar]
- Loeliger E. A., Meuwisse-Braun J. B., Muis H., Buitendijk F. J., Veltkamp J. J., Hemker H. C. Laboratory control of oral anticoagulants. Definition of therapeutic range in terms of different thromboplastin preparations. Thromb Diath Haemorrh. 1970 Jun 30;23(3):569–584. [PubMed] [Google Scholar]
- Miale J. B., LaFond D. Prothrombin time standardization. Proposal of the Standards Committee, College of American Pathologists, Subcommittee on Coagulation Reagents. Am J Clin Pathol. 1969 Aug;52(2):154–160. doi: 10.1093/ajcp/52.2.154. [DOI] [PubMed] [Google Scholar]
- Miale J. B., Lafond D. J. 1963 prothrombin time test survey, College of American Pathologists, Standards Committee, Subcommittee on Coagulation. Am J Clin Pathol. 1967 Jan;47(1):40–59. doi: 10.1093/ajcp/47.1.40. [DOI] [PubMed] [Google Scholar]
- Poller L., Thomson J. M. The interpretation of prothrombin results: a national survey. Br J Haematol. 1969 Jan-Feb;16(1):31–37. doi: 10.1111/j.1365-2141.1969.tb00376.x. [DOI] [PubMed] [Google Scholar]
- Zucker S., Cathey M. H., West B. Preparation of quality control specimens for coagulation. Am J Clin Pathol. 1970 Jun;53(6):924–927. doi: 10.1093/ajcp/53.6.924. [DOI] [PubMed] [Google Scholar]