Direct measurement of unfractionated heparin using a biochemical assay
| Autor: | Danial E. Baker, Christopher M. Starr, William A. Dittman, Gordon Ens, John C. Klock, Lyle D. Broemeling, Marcia R. Mielke, John R. White, Matt Wacksman, Sylvia A. Oliver, Dawn Devereaux, Patrick R. Gavin, C. Harold Mielke |
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| Rok vydání: | 2000 |
| Předmět: |
Electrophoresis
Endogeny Urine 030204 cardiovascular system & hematology Pharmacology Sensitivity and Specificity 03 medical and health sciences 0302 clinical medicine Pharmacokinetics In vivo medicine Bioassay Animals Humans 030212 general & internal medicine business.industry Heparin Assay Hematology General Medicine In vitro Kinetics Biochemistry Biological Assay Cattle business medicine.drug |
| Zdroj: | Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/Hemostasis. 5(4) |
| ISSN: | 1076-0296 |
| Popis: | A number of investigations have noted that func tional biological assays for heparin are not always reliable and may not reflect the actual biochemical level of heparin in pa tients receiving anticoagulant therapy. This creates the possi bility that patients receiving anticoagulant treatment may have an excess or deficiency of circulating levels of heparin. To address this problem, we have developed a direct biochemical measurement of heparin. The heparin assay uses fluorophore assisted carbohydrate electrophoresis (FACE) to directly mea sure the predominate disaccharide of unfractionated heparin. In this study, unfractionated heparin was measured in vitro throughout a wide range of heparin concentrations in plasma. Seven in vivo pharmacokinetic studies in five normal subjects given 3,000 USP units of unfractionated heparin intravenously showed a three-phase elimination process with higher peak plasma levels and shorter elimination times than predicted from previous studies. At these doses, heparin is largely eliminated intact through urinary excretion. Body weight has a significant effect on heparin kinetics. When we compared the direct bio chemical assay with two biological clotting assays, we found the latter can overestimate biochemical heparin concentrations. The FACE assay, due to its sensitivity, is also able to measure circulating levels of endogenous heparin in plasma and urine. Direct heparin measurement using the FACE technique is prac tical and useful for studies of the correlation of biochemical and biological activities. |
| Databáze: | OpenAIRE |
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