人類基因體計畫的完成，基因治療已成為醫學研究的重要組成部分。目前有許多載體可增加轉染及基因表現，包含病毒和非病毒性載體，雖然病毒性載體有較佳轉染效率，但有一些免疫性和高毒性問題，因此多數研究焦點在如何使非病毒基因載體有更好效果。而基因治療過程是將具療效質體DNA複合體送進細胞質中，質體DNA經質子海綿效應釋出，而最終目的是經由核孔複合體(nuclear pore complexes)進入細胞核表現蛋白質。本研究主要材料為生物可分解性高分子poly(lactide-co-glycolide)(PLGA)及polyethylenimine (PEI)，以Polyvinyl Alcohol(PVA)當安定劑，利用Emulsion - diffusion - evaporation的技術製成帶正電性的奈米微粒，利用掃描式電子顯微鏡(SEM)、原子力顯微鏡(AFM)、動態光散射粒徑分析儀(DLS)及表面電位分析儀分析正電性奈米顆粒的粒徑形態與大小及表面之電位，再以膠體電泳分析以瞭解正電性奈米顆粒對DNA的包覆能力，並研究無機離子對於正電性奈米微粒在細胞轉染及毒性變化趨勢。中文摘要 Human Genome Project completed,gene therapy has become a major part of medical research. There are many carriers to increase the transfection and gene expression, including viral and non-viral vector. Although viral carriers have better transfection efficiency than non-viral vector, but some problems as immunogenicity and high toxicity also occur. Consequently, the majority of research in non-viral gene therapy has been focused on developing more efficient vectors. The gene therapy is the process of plasmid DNA complex taken to the cytoplasm, plasmid DNA released by the proton sponge effect, while the ultimate goal is through the nuclear pore complex into the nucleus for protein expression. The aim of this study is the preparation of PEI 25K and poly(lactide-co-glycolide) (PLGA) nanopaticles formed by an emulsion method(emulsion-diffusion-evaporation) using PVA as a stabilizer. The particles size was characterized by atomic force microscopy (AFM), scanning electron microscopy(SEM) and dynamic light scattering (DLS). Zeta potential and gel electrophoresis studies were also performed to understand surface properties of carrier and their ability to bind negatively charged DNA. We also studied the effect of the addition of inorganic ions into polymer/DNA solution in transfection and toxicity of the cell.
