Fabrication of polyurethane - Heparinized carbon nanotubes composite for heart valves application

Abstract

In this study, nanocomposites based on polyurethane -carbon nanotubes modified with heparin was made to use in heart valves which was then modified through sulfuric acid and nitric acid oxidization. The next step was acylation reaction that replaced with chlorine molecules. Then amine groups attached to nano fillers in order to physical reaction of heparin molecules. The functionalized carbon nanotubes were characterized using fourier transform infrared spectra (FTIR), elemental analysis and thermogravimetric analysis (TGA) assessments. The morphology of nanocomposites was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In addition, dynamic mechanical thermal analysis (DMTA) used to determine thermo-mechanical properties of nanocomposites. To observe the effect of grafted heparin to the surface of carbon nanotubes, the hydrophilicity properties were observed through contact angle measurement, and to evaluate activation grafted heparin the activated partial trombobelastine time (APTT) test was performed. Finally, to investigate the effect of nanocomposites on blood components such as platelet, platelet adhesion test was performed on the surface of nanocomposites. The results revealed that occurrence of successful function-alization reaction. Heparin is a sulfated drug that has a hydrophilic property. The test results showed that the hydrophilicity properties were enhanced by increasing the amount of heparin that confirms heparin molecules grafted on the surface of nanoparticles successfully. The APTT test also showed the grafted heparin was acti-vated. Examination of platelet adhesion on the surface of heparinized nanocomposites revealed that with increasing the percentage of heparin in nanocomposites, platelet adhesion and accumulation on the surface of nanocomposites decreased, making it a promising candidate for further studies towards heart valve applications.