DNA已被證實能夠作為不同尺寸大小銀奈米簇的合成模板，這類以DNA為合成模板的銀奈米簇已被廣泛的應用在金屬離子、生物小分子的偵測與生物造影上，但以DNA作為合成模板的金奈米簇卻仍是一大挑戰，目前為止僅有少數文獻有提及。
本研發展出一套藉由紫外光輔助、簡單、且無需使用NaBH4並能夠大量生產的一步合成法，合成以多腺苷(poly-adenosine, A30)為合成模板的金奈米簇，所得的多腺苷包覆金奈米簇其螢光放光波長為475 nm；藉由粒徑層析證實當多腺苷包覆住金奈米簇時，整個結構會較多腺苷時更為剛性，多腺苷在反應中扮演著避免金原子聚集成尺寸較大的金奈米粒子的穩定劑，而在經過一連串的實驗後，證實紫外光在citrate離子還原金離子前驅物的反應上扮演著關鍵角色；此外本研究設計一段包含金奈米簇合成端-多腺苷(A30)與偵測端的單股核苷酸序列，可搭配SYBR GREEN I (SG)開發出一種金奈米簇螢光比例法探針，能夠靈敏高選擇性地偵測偵測端的互補序列，當偵測端的互補序列與偵測端完全互補雜交時，該金奈米簇螢光比例法探針會產生475 nm與525 nm兩道螢光，可藉由此兩道螢光強度的比值對偵測端的互補序列進行定量；此外汞離子與金奈米簇表面金一價的作用力會造成金奈米簇的螢光消光，而酵素水解反應所產生的胺基硫醇分子會對金奈米簇進行蝕刻而使金奈米簇的螢光消光，因此本螢光探針亦能夠運用在汞離子與酵素的檢測；上述三種螢光比例法偵測方法也成功的使用在真實樣品的偵測上。

DNA sequence has been used in synthesis of silver nanoclusters that play a role of template in decade in decade. The DNA-templated silver nanocluster has been widely applied at sensing of metal ion, biomolecular and bio-image. But there is a challenge in synthesis of gold nanoclusters by using DNA sequence as a template.

In this study, we develop a new approach that UV light-assisted, facile, one-pot, NaBH4-free and boundary way to synthesize gold nanoclusters by using poly-adenosine as a template, and get the poly-adenosine stabilized gold nanoclusters that have an emission at 475 nm under the excitation of 280 nm. Under a series of experiment, we definit the UV light play an important role in reduction reaction of gold ion by citrate ion. In size-exclusion chromatogaph(SEC), we can find the structure of poly-adenosine is more compact after the formation of poly-adenosine stabilized gold nanoclusters, it provide an evidence that poly-adenosine is a stabilizer for preventing gold atom aggregate into gold nanoparticles and forming of gold nanoclusters. On the other hand, we design a sequence contain poly-adenosine and specific DNA sequence to synthesize a poly-adenosine stabilized gold nanoclusters of containing specific DNA sequence, and it can combine with SYBR GREEN I to provide a ratiometric fluorescent sensors. This ratiometric fluorescent sensors provide a sensitivie and selective detection for specific DNA sequence, thiol-relative enzyme and mercury ion by hybridization of DNA, etching of thiol and metallophilic interactions, and successfully used in real sample.

論文審定書 i
論文公開授權書 ii
謝誌 iii
摘要 iv
ABSTRACT v
目錄 vi
圖次 viii
表次 xi
縮寫表 xii
第壹章 序論 1
一 金奈米簇 1
二 金奈米簇合成方法 1
2-1 上至下(top-down) 2
2-2 下至上(bottom-up) 2
三 金奈米簇光學性質 6
3-1 尺寸效應 6
3-2 配位基效應 6
3-3 結構與電荷效應 7
四 光化學還原反應 8
第貳章 紫外光輔助合成多腺苷包覆金奈米簇 9
一 研究動機 9
二 實驗部分 10
2-1 實驗藥品 10
2-2 儀器設備 12
2-3 實驗操作與藥品配置 15
三 結果與討論 19
3-1 紫外光輔助合成多腺苷包覆金奈米簇反應機制之探討 19
3-2 多腺苷包覆金奈米簇之光學性質 43
四 結論 50
第參章 設計多腺苷包覆金奈米簇應用在螢光比例法偵測汞離子酵素活性與特定核苷酸序列 51
一 前言 51
1-1 金奈米簇的應用 51
二 研究動機 58
三 實驗部分 58
3-1 實驗藥品 58
3-2 儀器設備 61
3-3 實驗操作 62
四 結果與討論 67
4-1 多腺苷包覆金奈米簇以螢光比例法偵測特定核苷酸序列 67
4-2 多腺苷包覆金奈米簇以螢光比例法偵測乙醯膽鹼酯酶 76
4-3 多腺苷包覆金奈米簇以螢光比例法偵測汞離子 84
五 結論 90
第肆章 參考文獻 91

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