A study evaluating clotting under various conditions with thromboelastography (TEG) and turbidimetry concluded that these 2 methods are distinct and should be used as synergistic characterization tools.
The findings were presented by biomedical engineering doctoral student Ziqian Zeng and colleagues of the Indiana University School of Medicine in Indianapolis and the Weldon School of Biomedical Engineering at Purdue University in West Lafayette, Indiana, at the Thrombosis & Hemostasis Summit of North America (THSNA) 2020 Virtual Conference.
“Understanding clot formation under diverse conditions can benefit clinical diagnosis of thrombosis as well as drug development,” said Mr Zeng.
The team created a simplified fibrinogen/thrombin clot model wherein high purity (>90%) thrombin and fibrinogen from human or bovine were mixed at different concentrations and under different clotting conditions, such as varying concentration of albumin, pH, and ionic strength. To determine the effects of these variables on clot strength and fibrin structure, they monitored thrombin-mediated fibrin formation via turbidimetry (via spectrometry using a Spectramax M5 microplate reader at room temperature) and TEG (Haemonetics TEG®5000 Analyzer with Software Version 4 at 37°C).
The investigators found that increasing thrombin concentration (0-10 U/mL), ionic strength (0.05-0.3 M), pH (5.5-8.1), and lowering albumin concentration (100-0 mg/mL) decreased clot turbidity and increased clot strength using species-matched fibrinogen and thrombin. Similarly, clot turbidity and clot strength increased with increasing fibrinogen concentration (1-5 mg/mL) in species-matched and cross-species combinations.
“TEG and turbidimetry tracked similarly under some clotting conditions; however, these assays measure clot formation via 2 distinct methods and are best utilized as synergistic characterization tools,” concluded the authors.
Their future work will focus on studies of other blood components known to affect clot formation, including platelets, red blood cells, and crosslinking fibrin by adding factor XIII and calcium.
Zeng Z, Fagnon M, Chakravarthula TN, Alves N. Leveraging turbidimetry and thromboelastography to characterize fibrin formation under diverse clotting conditions. Abstract presented at: THSNA 2020 Thrombosis & Hemostasis Summit of North America; October 27-30, 2020. Abstract 48.