為了提升陽離子型聚酯之轉染效率，合成了聚(胺基甲酸酯-酯) (PUE)含有胺基甲酸酯及酯的官能基於主鏈，導入三級胺之官能基於側鏈的之共聚合物，而利用新合成之聚酯類(PEE)此聚酯含有酯及三級胺分別於主鏈及側鏈來當作對照。利用動力光學散射儀測定此兩種陽離子型高分子;皆可以與DNA形成奈米級的複合體，從實驗結果中得到PUE與PEE形成複合體，此時粒徑大小約為80-115 nm及170-180 nm且帶正電，和DNA之重量比分別為2/1與 20/1 (polymer/DNA)。水解實驗中可得到PUE水解半生期為20小時。且從緩衝實驗可得知此高分子具有不錯的緩衝效率。最後利用COS-7細胞株做毒性測試與PEI做比較可得到一個較低毒性的結果。從上述結果中可得知此高分子可應用於基因治療且可供日後研究之材料。 To improve the transfection efficiency of cationic polyester, we synthesized poly (urethane-co-ester) (PUE) bearing urethane and ester linkages in the backbone and tertiary amines in the side chain, and polyester (PEE) bearing ester linkages in the backbone and tertiary amines in the side chain. Both poly (urethane-co-ester) (PUE) and polyester (PEE), readily self-assembled with the plasmid DNA (ρCMV-βgal) in HEPES buffer, were characterized by dynamic light scattering, zeta-potential. The results revealed that PUE and PEE were able to combine with DNA and yield complexes with positive charge of size around 80-115 nm and 170-180 nm at a mass ratio (W/W) of 2/1 and 20/1, respectively. The degradation studies indicated that the half-life of PUE in HEPES buffer is 20 hours. Titration studies were performed to determine the buffering capacities of the polymers. In addition, the COS-7 cell viabilities in the presences of PUE, PEE, and PEI were studies. In this, article, PUE seemed to be a novel cationic poly (urethane-co-ester) for gene delivery and an interesting candidate for further study.