Developing a blood-compatible material means not merely synthesizing a suit- able polymer, which l is nontoxic, sterilizable, noninflammatory with no adverse immune response, easily fabricable and nondegradable with stable mechanical strength for a prolonged period of time, and giving it a form of a prosthesis, but it is also equally important to understand polymer surface/blood component interactions at the interface, since surface-induced 2 thrombosis and embolism are the main obstacles to the use of nonbiological materials. Once a foreign surface comes in contact with blood, it is immedi- ately altered by the adsorption of plasma proteins, and the nature of the pro- tein adsorbed may affect the fate of material toward blood compatibility. Certain proteins 3,4, e.g., albumin, discourage platelet adhesion, but others, like y-globulins and fibrinogen, encourage platelet adhesion and enhance fur- ther thrombosis. Therefore, such initial events, which are dependent on the physicochemical nature of the surface, play a major role for the acceptance or rejection of the material. Adjusting these physicochemical parameters to cer- tain processing variations is also an important consideration 5.
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