基因治療研究的興起，DNA 與 siRNA 在基因治療上已經被廣泛的研究，並以病毒性及非病毒性載體來增強基因之轉染表現。一般常見的高分子微胞通常是由兩性共聚物( amphiphilic block copolymers )構成，而本研究設計以樹枝狀聚胺基甲酸酯高分子 Polyurethane Dendrimers(PUAD)作為外圍親水端，而因樹枝狀高分子外圍接枝胺基，而有正電荷，故對此材料進行測試，確認是否具有作為基因傳輸載體的潛力，生物可分解材料聚乳酸-甘醇酸共聚合物(Poly(D,L-lactide-co-glycolide(PLGA))則作為內部疏水核心。本研究以不同世代(generation)的 PUAD(G 2.0、3.0)與 PLGA，以脫水的方式來合成兩性共聚物。利用傅立葉紅外線光譜儀(FT-IR)與核磁共振光譜儀(NMR)確認其化學結構。並進行以下性質研究：其粒徑大小與電位、與 DNA 複合之能力、細胞毒性、與轉染能力。綜合以上研究資料我們發現 PUAD-PLGA 可以成為有潛力的基因非病毒型載體。 Gene therapies using DNA and siRNA have been widely investigated in fundamental research. There are many methods to increase the transfection and gene expression including viral and non-viral vectors. Due to many drawbacks of viral vectors, non-viral carriers became another choice for gene therapy. Generally, the polymeric micelles were usually composed of amphiphilic block copolymers. The research was designed to use polyurethane dendrimers(PUAD) as a hydrophilic periphery. Because of the dendrimers with cationic characteristic, therefore, we conduct some test on the polymeric micelles to make sure that their potential to be a transfection vector. Biodegradable material poly(D,L-lactide-co-glycolide)(PLGA) was used as a inter hydrophobic core and reduced the toxicity of cationic PUAD. In this study, we used different generations of PUAD (G 2.0, 3.0) and PLGA to form amphiphilic block copolymers by dehydration reaction and their chemical structures were confirmed using FT-IR and NMR. The following tests were to evaluate the characteristics of PLGA-PUAD micelles: DLS to analyze its particle size and zeta-potential, electrophoresis, cytotoxicity, and transfection efficiency. It was found that the PUAD-PLGA can become a potential non-viral gene vectors based on the above results.
