Related Experiment Video
Updated: Jul 8, 2026
Leveraging Turbidity and Thromboelastography for Complementary Clot Characterization
Published on: June 4, 2020
The fibrinogen functional turbidimetric assay
1Department of Clinical Chemistry, Central Laboratory, University Hospital, Marburg, Germany. thstief@med.uni-marburg.de
Hitherto, clinical fibrinogen methods were based on coagulation seconds, with assay conditions not similar to a plasma milieu. The fibrinogen functional turbidimetric assay included 50 microL citrated plasma + 100 microL 300 mIU/mL thrombin, 400 microg/mL polybrene, and 6% albumin-phosphate-buffered saline; an increase in absorbance at 405 nm/5 min at room temperature (or 2 minutes at 37 degrees C) was observed. In all, 6% albumin in the fibrinogen functional turbidimetric assay reagent abolishes falsely elevated fibrinogen to fibrin turbidity in hypoproteinemic plasma samples. This assay can detect fibrinogen activity of 250% to 300% of normal, the lower detection limit being 7% of normal (0.2 g/L). The normal range of this assay is 100% +/- 20% (mean value +/- 1 SD; coefficient of variations <4%). This assay imitates fibrinogen to fibrin conversion in clotting blood plasma; it is independent of plasmatic albumin or heparin and can be performed everywhere. This assay has a diagnostic value in pathology-disseminated intravascular coagulation and in assessing risk for atherothrombosis.
Hitherto, clinical fibrinogen methods were based on coagulation seconds, with assay conditions not similar to a plasma milieu. The fibrinogen functional turbidimetric assay included 50 microL citrated plasma + 100 microL 300 mIU/mL thrombin, 400 microg/mL polybrene, and 6% albumin-phosphate-buffered saline; an increase in absorbance at 405 nm/5 min at room temperature (or 2 minutes at 37 degrees C) was observed. In all, 6% albumin in the fibrinogen functional turbidimetric assay reagent abolishes falsely elevated fibrinogen to fibrin turbidity in hypoproteinemic plasma samples. This assay can detect fibrinogen activity of 250% to 300% of normal, the lower detection limit being 7% of normal (0.2 g/L). The normal range of this assay is 100% +/- 20% (mean value +/- 1 SD; coefficient of variations <4%). This assay imitates fibrinogen to fibrin conversion in clotting blood plasma; it is independent of plasmatic albumin or heparin and can be performed everywhere. This assay has a diagnostic value in pathology-disseminated intravascular coagulation and in assessing risk for atherothrombosis.
