基因治療是一種藉由導引一段外來基因片段至目標細胞進行治療的過程。基因治療主要針對是多種遺傳及特定的疾病。利用小分子干擾核糖核酸 (siRNA) 靜默多重抗藥性蛋白 (MDR) 的技術，提供一個全新的機會去克服目前化療上遇到的抗藥性問題。在本篇研究中，利用氧化石墨稀 (GO), 聚乙烯亞胺 (PEI) 和聚乙二醇 (PEG) 作為起始材料，並藉由水熱法一步合成，製備出可進行雙重傳遞的載體，最終產物奈米平台rGO-PEI/PEG 具有低毒性且可在重量比 3.4的條件下有效縮合上siRNA。此外rGO-PEI/PEG具有高載藥量 (Dox, ~0.49 mg/mg) 的特點並能利用光熱效果在細胞質中釋放藥物。藉由照射適當的近紅光雷射，rGO-PEI/PEG載藥後的載體可以結合光熱治療和化療達到增強治療腫瘤和癌細胞的療效。利用可同時載負雙重藥物 (DOX和siRNA) 的載體rGO-PEI/PEG，達到治療上雙藥的協同作用，並加上雷射治療未來可以增強有抗藥性的癌細胞的治療。此外本篇論文也針對石墨稀功能化及在藥物和基因傳遞上的研究多加探討。

Gene therapy is a process of introducing foreign genomic materials into target cells to elicit a therapeutic benefit. A diverse array of inherited and acquired diseases are targets of gene therapy. To overcome the multidrug resistance (MDR), one of the major impediment against curative cancer chemotherapy, the application of small interfering RNA (siRNA) provide a new opportunity for specific gene-silencing of MDR-associated proteins. In this study, a simple and novel approach is presented for constructing a dual delivery vector through a one-pot hydrothermal reaction, using graphene oxide (GO), polyethylenimine (PEI) and polyethylene glycol (PEG) as starting materials. The resulting nanoplatform, rGO-PEI/PEG exhibited minimal toxicity and could effectively complex siRNA at a W/W ratio above 3.4. Additionally, rGO-PEI/PEG was capable of high drug loading (doxorubicin, ~0.49 mg/mg) and photothermally triggered cytosolic drug delivery. With optimal near-infrared laser irradiation, the drug-loaded rGO-PEI/PEG demonstrated an enhanced antitumor efficacy in cancer cells through combined photothermal effect and chemotherapy. The synergistic potential of dual drugs (doxorubicin and siRNA)-loaded rGO-PEI/PEG in combination with laser irradiation will next be explored to augment the therapeutic effect in MDR cancer cells. The advances described above will complement our knowledge of graphene functionality and serve to guide its application in gene/drug delivery.

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