我們開發液晶液滴用於即時檢測水溶液中金屬離子，在我們的研究中分為兩部分，在第一部分我們摻雜4'-(octyloxy)-[1,1'-biphenyl]-4-carboxylic (8OBCA) 在5CB中，利用8OBCA作為兩性分子穩定液晶液滴。當加入含有金屬離子的溶液時，其組態會從radial轉變為bipolar，該液晶液滴可以用於檢測鎂、鈣、鎘、錳、鈷、鉛離子。在第二部分我們將摻雜物8OBCA改為對汞離子具有專一性的配基5-(pyridine-4-yl)-2-(5-(pyridin-4-yl)- thiophen-2-yl)thiazole (ZT)，在含有汞的溶液中ZT會與汞離子形成錯合物而導致組態從radial轉變為bipolar，藉由觀察此現象可以對汞進行專一性檢測且其偵測極限為25 μM，該系統也能在真實水樣中檢測汞離子。由於液晶液滴的變化可藉由肉眼判斷，因此該系統可作為一般民眾檢測水溶液中汞離子的方法。

We report the liquid crystal (LC) droplets which are able to detect the metal ions in water in real-time. We divide into two parts in our research, in first part, we doped nematic LC (5CB) with 4'-(octyloxy)-[1,1'-biphenyl]-4-carboxylic acid (8OBCA) which acts as the amphiphilic molecules decorated at LC/aqueous interface to stabilize the droplets. When the carboxylic groups on the surface of LC droplets interacted with the metal ions in water, the configurational transition of LCs from radial to bipolar was observed. Our results showed that the LC droplets are able to detect a series of metal ions including Mg2+, Ca2+, Cd2+, Mn2+, Co2+, and Pb2+. In second part, We changed dopant into a mercuric ion-selective ligand, 5-(pyridine-4-yl)-2-(5-(pyridin-4-yl)- thiophen-2-yl)thiazole (ZT). When the LC droplets were dispensed in the solution containing Hg2+, the formation of Hg2+/ZT complexes lead to a distinct radial-to-bipolar configurational transition of LC droplets. By using this mechanism, the LOD of Hg2+ can be detected is 25 μM, and it has high selectivity for detecting Hg2+. Besides, we also demonstrated that this system can be used to detect Hg2+ in tap water and pond water. Because the signals of LC droplets can be differentiated through the naked-eye under ambient light, it provides a simple approach for normal users to be aware of the presence of Hg2+ at localized aqueous environment.

總目錄
第一章 緒論 ................................................................................................... 1
1-1 液晶感測器 ........................................................................................... 1
1-1-1 液晶 ............................................................................................... 2
1-1-2 液晶感測器檢測機制 ................................................................... 6
1-1-3 液晶感測器種類 ........................................................................... 8
1-2 重金屬 ................................................................................................. 17
1-2-1 重金屬汙染 ................................................................................. 17
1-2-2 重金屬離子的檢測方法 ............................................................. 21
1-3 研究動機 ............................................................................................. 23
第二章 實驗方法與材料 ............................................................................... 24
2-1 實驗藥品與器材 ................................................................................. 24
2-2 實驗儀器 ............................................................................................. 26
2-3 實驗方法 ............................................................................................. 27
2-3-1 製備塗覆DMOAP 載玻片 ......................................................... 27
2-3-2 製備空白載玻片 ......................................................................... 27
2-3-3 8OBCA 部分 ................................................................................. 28
2-3-4 ZT 部分 ......................................................................................... 29
V
2-3-5 金屬離子部分 ............................................................................. 31
2-3-6 液晶液滴的檢測與鑑定 ............................................................. 31
第三章 結果與討論 ....................................................................................... 33
3-1 玻璃基板的選定 ................................................................................. 33
3-2 含8OBCA 之液晶液滴 ...................................................................... 34
3-2-1 含8OBCA 之液晶液滴最佳條件建立 ...................................... 34
3-2-2 含8OBCA 之液晶液滴檢測機制 .............................................. 41
3-2-3 含8OBCA 之液晶液滴特異性測試 .......................................... 42
3-2-4 含8OBCA 之液晶液滴靈敏度測試 .......................................... 44
3-2-5 含8OBCA 之液晶液滴真實樣品測試 ...................................... 46
3-3 含ZT 之液晶液滴 .............................................................................. 47
3-3-1 不同界面活性劑對含ZT 之液晶液滴組態的影響 .................. 47
3-3-2 CTAB 濃度對含ZT 之液晶液滴組態的影響 ............................. 50
3-3-3 含ZT 之液晶液滴穩定度測試 .................................................. 51
3-3-4 汞離子對含ZT 之液晶液滴組態的影響 .................................. 52
3-3-5 含ZT 之液晶液滴特異性 .......................................................... 56
3-3-6 其他金屬離子對汞離子檢測的影響 ......................................... 57
3-3-7 含ZT 之液晶液滴靈敏度 .......................................................... 58
3-3-8 含ZT 之液晶液滴之汞離子定量 .............................................. 59
VI
3-3-9 pH值對含ZT 之液晶液滴特異性的影響 ................................. 60
3-3-10 pH 值對含ZT 之液晶液滴靈敏度的影響 ............................... 63
3-3-11 ZT 摻雜比例與CTAB 濃度對靈敏度的影響 ........................... 64
3-3-12 陰離子對含ZT 之液晶液滴靈敏度的影響 ............................ 66
3-3-13 含ZT 之液晶液滴真實樣品測試 ............................................ 67
3-3-14 含ZT 之液晶-水溶液系統與液晶液滴系統比較 ................... 69
第四章 結論與未來展望 ............................................................................... 70
第五章 參考資料 ........................................................................................... 72
VII
圖目錄
圖 1 液晶於偏光下的光學訊號 ..................................................................... 1
圖 2 液晶分子的構造 ..................................................................................... 3
圖 3 4-戊基-4'-氰基聯苯 (4-pentyl-4’-cyanobiphenyl, 5CB) 的結構 .......... 5
圖 4 桿狀型液晶示意圖 ................................................................................. 5
圖 5 圓盤型液晶示意圖 ................................................................................. 6
圖 6 液晶排列與光學訊號之關係圖 ............................................................. 7
圖 7 液晶-固體界面感測系統基本架構 ....................................................... 9
圖 8 (a) DMOAP (b) OTS 結構圖 ................................................................. 10
圖 9 液晶-水溶液界面感測系統 ................................................................. 11
圖 10 PAA-b-LCP 結構圖 ............................................................................. 12
圖 11 PNIPAM-b-LCP 結構 .......................................................................... 13
圖 12 製備液晶液滴的方法示意圖 ............................................................. 14
圖 13 液晶液滴常見的兩種組態圖 (箭頭表示缺陷點) 及示意圖 (黑色
虛線為液晶分子排列方向) .................................................................. 15
圖 14 穀胱甘肽結構圖 ................................................................................. 22
圖 15 芘的衍生物結構 ................................................................................. 22
圖 16 液晶滴液放置在 (a) 修飾DMOAP 玻璃基材與 (b) 未修飾玻璃基
材上的影像 ............................................................................................ 33
VIII
圖 17 4'-(octyloxy)biphenyl-4-carboxylic acid (8OBCA) 結構圖 ............... 34
圖 18 鹼滴定8OBCA 之UV-vis 圖譜 ........................................................ 35
圖 19 Henderson-Hasselbalch equation 校正曲線 ........................................ 36
圖 20 不同pH 值下含8OBCA 之液晶液滴組態變化............................... 37
圖 21 不同pH 值下含8OBCA 之液晶液滴粒徑大小............................... 38
圖 22 不同摻雜濃度下含8OBCA 之液晶液滴組態變化 ......................... 39
圖 23 不同摻雜濃度下含8OBCA 之液晶液滴粒徑大小 ......................... 40
圖 24 含8OBCA 之液晶液滴檢測金屬離子機制示意圖 ......................... 41
圖 25 含8OBCA 之液晶液滴特異性 .......................................................... 43
圖 26 含8OBCA 之液晶液滴檢測Mg2+之靈敏度 .................................... 44
圖 27 含8OBCA 之液晶液滴檢測Ca2+之靈敏度 ..................................... 44
圖 28 含8OBCA 之液晶液滴檢測Mn2+之靈敏度 .................................... 45
圖 29 含8OBCA 之液晶液滴檢測Co2+之靈敏度 ..................................... 45
圖 30 含8OBCA 之液晶液滴檢測Cd2+之靈敏度 ..................................... 45
圖 31 含8OBCA 之液晶液滴檢測Pb2+之靈敏度 ..................................... 45
圖 32 含8OBCA 之液晶液滴在自來水和池塘水中檢測Pb2+的靈敏度 . 46
圖 33 ZT 結構圖 ............................................................................................ 47
圖 34 CTAB 結構圖....................................................................................... 48
圖 35 SDS 結構圖 .......................................................................................... 48
IX
圖 36 tween-20 結構圖 .................................................................................. 48
圖 37 不同界面活性劑下液晶液滴組態 ..................................................... 48
圖 38 不同界面活性劑下含ZT 之液晶液滴組態變化 .............................. 49
圖 39 不同CTAB 濃度下含ZT 之液晶液滴組態 ..................................... 50
圖 40 含ZT 之液晶液滴粒徑大小 .............................................................. 51
圖 41 含ZT 之液晶液滴經過長時間組態 .................................................. 51
圖 42 含ZT 之液晶液滴對照組 .................................................................. 53
圖 43 含ZT 之液晶液滴檢測Hg2+之機制示意圖 ..................................... 53
圖 44 液晶液滴中ZT 錯合物之UV-vis 圖譜 ............................................ 54
圖 45 含ZT 之液晶加入Hg2+前與加Hg2+後之HPLC 層析圖 ................ 55
圖 46 含ZT 之液晶液滴特異性 .................................................................. 56
圖 47 含ZT 之液晶液滴之金屬干擾測試 .................................................. 57
圖 48 含ZT 之液晶液滴對Hg2+靈敏度 ..................................................... 58
圖 49 含ZT 之液晶液滴亮暗面積變化校正曲線 ...................................... 59
圖 50 含ZT 之液晶液滴在pH 4 下特異性 ................................................ 60
圖 51 含ZT 之液晶液滴在pH 7 下特異性 ................................................ 61
圖 52 含ZT 之液晶液滴在pH 10 下特異性 .............................................. 62
圖 53 含ZT 之液晶液滴在pH 4 下對Hg2+靈敏度 ................................... 63
圖 54 含ZT 之液晶液滴在pH 7 下對Hg2+靈敏度 ................................... 63
X
圖 55 含ZT 之液晶液滴在pH 10 下對Hg2+靈敏度 ................................. 64
圖 56 使用CTAC 作為界面活性劑含ZT 之液晶液滴對Hg2+靈敏度..... 66
圖 57 含ZT 之液晶液滴在真實水樣中檢測Hg2+的靈敏度 ..................... 68
XI
表目錄
表1 含ZT 之液晶加入Hg2+前與加Hg2+後之HPLC 數據 ....................... 55
表2 含ZT 之液晶液滴在不同摻雜濃度與不同CTAB 濃度下的偵測極限
................................................................................................................ 65
表3 不同水樣中電導值 ................................................................................ 68
表4 含ZT 之液晶-水溶液系統與液晶液滴系統比較 ............................... 69

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