Preparation Of Biomedical Porous Polyurethane Film Material And Evaluation Of Its Blood Compatibility

Polyurethane (PU) has a wide range of application in the field of biomedical materials especially in the field of tissue engineering because of its excellent mechanical properties and biocompatibility. As scaffold for tissue engineering, it should be biocompatibility, non-cytotoxic, non-immune and has a three-dimensional porous structure to facilitate cell adhesion, proliferation and differentiation. The blood compatibility is particularly important for vascular tissue engineering materials.Aspirin and heparin are widely used drug as anticoagulant to improve the blood compatibility of materials. Here, the polyvinyl alcohol-g-1-(acetylsalicylyl) benzotriazole (PVA-ASBA) was synthesized firstly refers to previous work. Then the product above, acted as anticoagulant additive, was added into PU/Dimethyl sulfoxide (DMSO) system to produce PU/PVA-ASBA highly porous membrane by TIPS method. Moreover, porous PU-heparin membrane was obtained by low-temperature plasma method which can provide long lasting antithrombogenicity. Heparin is also interact with growth factor VEGF that has heparin-binding domain, which enables sustained-release VEGF. Additionally, porous PU/PLGA membrane was prepared by TIPS method. The porous PU/PLGA membrane was also grafted heparin molecule on the surface to improve the blood compatibility.The surface properties of the porous PU, PU/PVA-ASBA, PU-heparin and PU/PLGA membranes were examined with infrared spectroscopy (ATR-FTIR), water contact angle (WCA), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS).The blood compatibility of the porous membranes were evaluated by red blood cell and platelet-rich plasma adhesion study, APTT/PT/TT clotting time test, hemolysis test, red blood cell morphology test. The experimental result indicates that the modified porous membranes exhibit more excellent blood compatibility compared to the porous PU membrane.