Vol. 33, No. 4, 2003
Issue release date: July–August 2003
Pathophysiol Haemost Thromb 2003;33:202–205
(DOI:10.1159/000081506)
Original Paper
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Ecarin Chromogenic Assay – A New Method for Quantitative Determination of Direct Thrombin Inhibitors Like Hirudin

Lange U.a · Nowak G.b · Bucha E.a
aHaemoSys GmbH and bResearch Unit ‘Pharmacological Hemostaseology’, Medical Faculty, Friedrich Schiller University, Jena, Germany
email Corresponding Author


 goto top of outline Key Words

  • Hirudin
  • Thrombin inhibitor
  • Ecarin chromogenic assay
  • Ecarin clotting time
  • Argatroban

 goto top of outline Abstract

A new sensitive and precise method for quantitative determination of direct thrombin inhibitors is described, the ecarin chromogenic assay (ECA). Ecarin is used as the specific prothrombin-activating principle. The cleavage of a chromogenic substrate by meizothrombin is inhibited in a concentration-dependent fashion by direct thrombin inhibitors. For the ECA, the linear measuring range is about 0.1–3.0 μg hirudin/ml plasma. Coefficients of variations between 2.3 and 4% over the whole concentration range were achieved. The ECA has proved to be more sensitive than the compared tests (ecarin clotting time and a thrombin-based chromogenic assay); a detection limit of 0.011 μg hirudin/ml and a quantitation limit of 0.032 μg hirudin/ml were calculated. The ECA is independent of the variations of the coagulation variables fibrinogen and prothrombin. Neither heparin nor oral anticoagulants interfere with the ECA.

Copyright © 2004 S. Karger AG, Basel


 goto top of outline References
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    External Resources

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    External Resources

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 goto top of outline Author Contacts

Dr. Ute Lange
HaemoSys GmbH
Winzerlaer Strasse 2
DE–07745 Jena (Germany)
Tel. +49 36 41 50 83 21, Fax +49 36 41 50 83 01, E-Mail u.lange@haemosys.de


 goto top of outline Article Information

Received: July 26, 2004
Accepted after revision: September 14, 2004
Number of Print Pages : 8
Number of Figures : 7, Number of Tables : 2, Number of References : 28


 goto top of outline Publication Details

Pathophysiology of Haemostasis and Thrombosis

Vol. 33, No. 4, Year 2003 (Cover Date: July-August 2003)

Journal Editor: Rosing, J. (Maastricht)
ISSN: 1424–8832 (print), 1424–8840 (Online)

For additional information: http://www.karger.com/pht


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