Abstract
The authors have evaluated blood compatibility of in situ heparin immobilized and sulfonated polyurethane (PU) using our epifluorescent video microscopy (EVM) combined with parallel plate flow chamber. EVM system measured the amount of adhered platelet on the surface under the flow of human whole blood containing mepacrine labelled platelets perfused at a wall shear rate of 100/sec every one minute intervals for 20min. Platelet activation (β-TG) and complement activation (C3a) were also measured. Both heparin immobilized and sulfonatedPUs showed significantly lower levels of platelet adhesion than the control PU.The β-TG levels of these modified PUs also correspond to the results of the platelet adhesion. As for the complement activation, while sulfonated PU and the control PIP showed a higher levels of complement activation. In situ surface modification techniques, which utilize either ozone oxidation or photo reaction are useful in a variety of medical devices even of a complex design, such as a membrane oxygenator or artificial heart.
