Na+-γ-poly(glutamic acid) (PGA)為一具有水溶及生物可分解性的聚胜，本研究利用其與聚乙烯醇製得一混摻膜。在室溫下且不需任何化學藥劑的條件下，PGA 和PVA 即可形成水膠。由熱性質測試的結果，在PVA中增加PGA的含量可提升混物之熱安定性。隨著PGA添加降低膨潤度而水膠之保水率增加。PVA則較PGA/PVA水膠之抗張強度高約6~24.5%，但PGA/PVA複合水膠的斷裂伸長量則較PVA高1.2~1.74倍。而蛋白質及血小板的吸收方面會隨著PGA的增加而下降，而延長水膠之凝血時間，本實驗中也以L929試驗標準證明水膠不具細胞毒性。綜觀所有結果，顯示PGA/PVA之複合水膠，其抗凝血性、生物相容性及機械性質應用在血液接觸的生醫材料上相當有潛力。

Na+-γ-poly(glutamic acid) (PGA), a water-soluble and biodegradable polypeptide, was chosen to fabricate the PGA/polyvinyl alcohol (PVA) blending membranes. By mixing PGA and PVA together, a hydrogel would form in aqueous medium at room temperature without any chemical treatment. From the results of all testing, blending PGA with PVA can improve the all of PVA. Although the swelling ratio decreased with the PGA addition, the water retention of blending hydrogel was enhanced. The mechanical strength of the PGA/PVA hydrogel membranes was about 6-24.5% lower than that of the PVA matrices, however the elongation rate was enhanced 1.2 to 1.74 times. The amount of protein adsorbed and platelets adhered on the blending membrane was significantly curtailed with increasing PGA content. The blood coagulation times were thus prolonged. The blending matrices were proven to be non-cytotoxic examined from L-929 fibroblast incubation. In addition, PGA/PVA also exhibited favorable for cytocompatibility. Overall results demonstrated that the PGA/PVA blending hydrogel exhibited antithrombogenicity, cytocompatibility, and mechanical properties, and would be very promising candidates for blood-contacting medical devices.

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