Tridib Chakraborty
Pronouns: he/him
Research Mentor(s): Orsolya Lautner-Csorba
Research Mentor School/College/Department: Surgery / Medicine
Program:
Authors: Tridib Chakraborty, Orsolya Lautner-Csorba, Morgan Caudil, Ryan Kauffman, Megan Stein, Josef Hill, Amada Burde, Gergely Lautner, Alvaro Rojas-Pena
Session: Session 2: 10:00 am – 10:50 am
Poster: 78
Abstract
Bivalirudin as a Direct Thrombin Inhibitor in a Polymer Surface Coating T Chakraborty; M Caudill; R Kauffman , BS ; M Stein , BS ; J Hill , MS ; A Burde , PhD ; G Lautner , PhD ; RH Bartlett , MD ; A Rojas – Pena , MD ; O Lautner – Csorba , PhD Objective : Direct Thrombin Inhibitors (DTI) such as Argatroban (Arg) or Bivalirudin (Bival) are frequently used systemically in extracorporeal life support (ECLS) as substitutes for heparin anticoagulation. Our laboratory has demonstrated the successful use of Arg in surfaces of extracorporeal circuits (ECCs). These circuits are designed to avoid the use of systemic anticoagulation and mitigate clotting and excess bleeding during ECLS. This study evaluates the viability of coating surfaces with Bival as an alternative to Arg by analyzing its thrombin inhibition capacity (TIC) in vitro. Methods: An isocyanate linker was used to immobilize Bival to the polymer CarboSil® and after precipitating the product with hexane and washing away the free linker, the substance was re-dissolved in tetrahydrofuran (THF ). Fourier-transform infrared spectroscopy (FTIR) was used to ensure proper bonding of Bival to CarboSil® via the isocyanate functional group. DTI functionality of the Bival/CarboSil® polymer was tested in vitro using an antithrombin chromogenic assay to measure product cleavage by thrombin into remaining peptides and free p – p-nitroanilide, as the chromophore. The absorbance difference was measured by a microplate reader at 405 nm and was used to evaluate its efficacy. The viability of the Bival coating on an extracorporeal circuit (ECC) was also assessed in an acute in vivo model. Results: FTIR data showed a decrease in the peak size (at 2250 cm -1 ) for the isocyanate group, demonstrating Bival bound to the linker and polymer. The antithrombin assay showed that the TIC for immobilized Bival was 1.0 µM/L which is ca. 2.5 times higher than previously reported Arg (TIC= 0.4 µM/L). These concentrations were evaluated using a standard curve with a range from 0 to 1 µM, where 1 µM means the highest thrombin inhibition. No significant clot formation was observed in the ECC after the 4 h-long model of thrombogenicity in rabbits. Conclusion: We report the first use of a novel surface-bound coating with Bivalirudin and demonstrate its high efficacy and feasibility for the potential prevention of thrombus formation in extracorporeal polymer surfaces. Future docking and structure-activity relationship (SAR) studies may be performed to learn about the molecule’s unique binding and biological capabilities. Tridib Chakraborty, undergraduate student; General Surgery, ECLS Laboratory B552 MSRBII, 1150 W. Medical Center Drive, Ann Arbor, MI 48109; chakratc; 734 – 615 – 5357; Faculty mentor: Orsolya Lautner – Csorba, PhD
