Thromb Haemost 1992; 67(04): 424-427
DOI: 10.1055/s-0038-1648464
Original Articles
Schattauer GmbH Stuttgart

A Collaborative Study to Establish an International Standard for Alpha-Thrombin

P J Gaffney
The National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, UK
,
A B Heath
The National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, UK
,
J W Fenton II
*   The Wadsworth Center for Laboratories and Research, New York State Department of Health, Empire State Plaza, Albany, New York, USA
› Author Affiliations
Further Information

Publication History

Received 19 June 1991

Accepted after revision 10 October 1991

Publication Date:
03 July 2018 (online)

Summary

Since 1975 an International Standard for Thrombin of low purity has been used. While this standard was stable and of value for calibrating thrombins of unknown potency the need for a pure a-thrombin standard arose both for accurate calibration and for precise measurement of thrombin inhibitors, notably hirudin. An international collaborative study was undertaken to establish the potency and stability of an ampouled pure a-thrombin preparation. A potency of 97.5 international units (95% confidence limits 86.5-98.5) was established for the new a-thrombin standard (89/ 588) using a clotting-assay procedure. Stability data at various elevated temperatures indicated that the standard could be transported and stored with no significant loss of potency.

Ampoules of lyophilised a-thrombin (coded 89/588) have been recommended as an International Standard for a-thrombin with an assigned potency of 100 international units per ampoule by the International Society for Thrombosis and Haemostasis (Thrombin and its Inhibitors Sub-Committee) in Barcelona, Spain in July 1990 while the Expert Committee on Biological Standardisation and Control of the World Health Organisation will consider its status at its next meeting in Geneva in 1991.

 
  • References

  • 1 Roberton I, Gaffney PJ, Bangham DR. Standard for human thrombin. Thromb Diath Haemorrh 1975; 34: 3-19
  • 2 Fenton II JW, Fasco MJ, Stackrow AB, Aronson DL, Young AM, Finlayson JS. Human thrombins. Production, evaluation and properties of a-thrombins. J Biol Chem 1977; 252: 3587-3598
  • 3 Fenton II JW, Landis BH, Walz DA, Finlayson JS. Human thrombins. In: Chemistry and Biology of Thrombin. Lundblad RL, Fenton II JW, Mann KH. (eds) Ann Arbor Science Publishers Inc; Ann Arbor, MI: 1977. pp 43-70
  • 4 Campbell PJ. International Biologicals Standards and Reference Preparations. 1. Preparation and presentation of materials to serve as standards and reference preparations. J Biol Stand 1974; 2: 249-258
  • 5 Finney DJ. Statistical Methods in Biological Assay. 3rd Edition. Griffin; London: 1978
  • 6 Kirkwood TBL. Geometric means and measures of dispersion. Biometrics 1979; 35: 908-909
  • 7 Kirkwood TBL, Tydeman MS. Design and analysis of accelerated degradation tests for the stability of biological standards. J Biol Stand 1984; 12: 195-224
  • 8 Gaffney PJ, Lord K, Brasher M, Kirkwood TBL. Problems in the assay of thrombin using synthetic peptides as substrates. Thromb Res 1977; 10: 549-556