Develop urea biosensor based on an ammonium electrode

口試委員會審定書 授權書 i 目錄 ii 圖表目錄 iv 中文摘要 v 英文摘要 vii 誌謝 x 第一章緒論 -1- 1-1 研究背景 -1- 1-2 研究目的與動機 -3- 1-3 論文架構 -4- 第二章 理論分析與探討 -6- 2-1生物感測器之種類功能介紹 -6- 2-2酵素固定化技術 -8- 2-3載體 -9- 2-3-1 氨與銨之簡介 -10- 2-3-2 銨離子選擇電極之選擇 -11- 2-3-3 銨離子選擇電極之特性參數探討 -11- 2-3-4 銨離子選擇電極離子干擾分析 -14- 2-4延伸式閘極感測場效電晶體之原理 -15- 2-5 尿素含量在臨床之探討 -16- 2-6 文獻探討 -17- 第三章 實驗方法與材料 -18- 3-1材料 -18- 3-2量測系統 -20- 3-3儀器與器材 -21- 3-4 感測器的製備 -22- 3-4-1 可繞性感測器的製備 -22- 3-4-2 銨離子感測電極的製備 -23- 3-4-3 銨離子尿素感測器的製備 -24- 第四章 結果與討論 -25- 4-1銨離子感測膜反應校正曲線和標準差 -26- 4-2銨離子電極對不同濃度尿素的反應 -28- 4-3不同緩衝液對於不同濃度尿素的反應趨勢 -29- 4-4 Tris是含EDTA對於尿素反應的比較 -31- 4-5 Tris有無含NH4Cl對於尿素反應的影響 -33- 4-6尿素濃度區間反應之選擇性 -35- 4-7銨離子選擇電極於尿素濃度區間4~8mg/dl之反應特性 -36- 4-8 銨離子選擇電極於尿素濃度區間1-2mg/dl之反應特性 -37- 第五章 結論 -39- 參考文獻 -41-[[abstract]]氨（NH3）是一種大氣或自然界水體中無所不在的化合物，是所有含氮物種中化學結構最簡單的化合物。在pH值小於8 的情況下，氨溶於水之後會和水分子作用而大部分以銨離子（NH4+）的形式存在，若是氨的含量過多之時，將會讓水體優養化，進而導致水體生態失去平衡。 在人體內，血漿中正常之尿素濃度為18-36 mg/dl，而臨床上尿素測量常以其含氮量表示，稱為尿素氮，1 mg/dl尿素氮相當於2.14 mg/dl尿素濃度，尿素氮會因其人體狀態之不同而顯現尿素濃度之不同，也因此量測血液中之尿素含量在臨床上是具有其意義的。 為檢測其環境(氨態氮)以及人體(尿素氮)之銨離子需求，本論文研究之電極所達到之最低檢測限如完善開發，將可對更低濃度尿素之環境或者人體血液尿液進行更準確之量測。 本論文利用延伸式ITO/PET離子感測場效電晶體製作耐用型的銨離子選擇電極，探討各個參數對於整體反應之影響，經過一些實驗之結果可得知銨根離子可偵測濃度為10-5 ~ 1M 之範圍，線性範圍約為0.99，平均感測度為55.09 mV / pNH4+ ，緩衝液部分利用PB以及Tris進行量測，利用Tris緩衝液可以使量測結果趨於穩定，在收集文獻過程中有些許文獻指出在緩衝液內加入EDTA會有更好的感測度，因此進行了加入及不加入EDTA的實驗，但發現不加入EDTA之反應更加的靈敏，因而採用不加入EDTA繼續進行研究，為了顯現此感測器的價值，也就是感測限比傳統型尿素感測器低，因而進行尿素濃度區間展開之實驗(1mg/dl~8mg/dl)，在此展開結果中可得知此電極在尿素濃度在低下的狀況下所得到之反應會比一般感測器來的更加靈敏，檢測限更低，在人體方面，未來可利用稀釋此種方式來對正常人體之尿素或血液將其稀釋至最佳檢測濃度，將可得到最為靈敏且可靠之反應結果。 在環境檢測中，莫過於水質汙染最為嚴重，因此對於水體的監控更能看出此感測器的價值，因水體中存在之銨離子所產生之尿素是微乎其微的，因此感測器檢測限低，可針對銨離子產生之低濃度尿素進行監測，獲得更加靈敏且可靠的結果，因此可用此感測器來對自然水體環境進行監控。 此感測器有著比一般感測器更低之檢測限度以及更佳的靈敏度，對於未來要監測環境中低濃度的尿素可以更迅速且靈敏的檢出，也可針對人體之血、尿液來進行監測，此電極未來如完善的開發，將可對環境及人體有著一大貢獻。 關鍵字:銨，生物感測器，銨離子選擇電極 論文外文摘要： Ammonia (NH3) is a compound that exists ubiquitously in the atmosphere and natural water and is the compound having the simplest chemical structure among the nitrogen-containing species. In the case of pH value below 8, as ammonia dissolves in water, it reacts with water molecules to form ammonium ions (NH4+) mostly. When there is too much ammonia dissolved in water, the water becomes eutrophic, leading to the aquatic ecological imbalance. In the human body, the normal urea concentration in the plasma is 18-36 mg/dl whereas in the clinical practice urea is most often measured in term of the amount of nitrogen, namely the urea nitrogen. The concentration of urea nitrogen of 1 mg/dl is equivalent to a concentration of urea of 2.14 mg/dl. Urea nitrogen varies according to the human body condition and reflects on the variation of urea concentration. Therefore, measuring the concentration of urea in blood can be a meaningful method to monitor the body condition in the clinical practice. For the demand of detecting the ammonium ions of the ammoniacal nitrogen in the environment and of the urea nitrogen in the human body, if the lowest detection limit of the electrode described in this research publication can be fully developed, further lower concentrations of urea in the environment or human blood and urine can be measured more accurately. In this publication, the extended ITO/PET ion-sensitive field-effect transistors are used to produce the durable ammonium ion-selective electrodes for investigating the impact to the overall reaction affected by each parameter. According to the results of several experiments, the concentration of ammonium ion in the range between 10-5 ~ 1M is detectable with a linear range of about 0.99 and the average sensibility is 55.09 mV / pNH4+. As for the buffer solution, PB and Tris buffer solutions are used for measurement whereas the use of Tris buffer can stabilize the measuring results. While researching the references, some references indicate that the sensitivity can be better by adding EDTA in the buffer solution. Therefore, experiments with EDTA added and without EDTA added in the buffer solutions were both conducted. However, the results show that the experiments without adding EDTA have better sensitivities to the reactions. Since then, the experiments proceeded without EDTA. In order to demonstrate the value of this sensor whose lowest detection limit is lower than that of a traditional urea sensor, experiments thus have been conducted with the interval expansion of urea concentration (1mg/dl ~ 8mg/dl). The expansion result shows that this electrode is more sensitive than a regular sensor in reacting to lower urea concentrations, and the detection limit of this electrode is also lower. For monitoring the human body condition, to apply this dilution method to dilute the urea or blood from a normal body to the most suitable concentration level for measurement will bring the most sensitive and reliable reaction result in the future. Nothing is more serious than the water pollution in the detection of the environmental hazards. Therefore, this sensor is even more valuable when it comes to the monitoring of the water bodies. Since the urea produced by the ammonium ions in the water bodies is found in trace quantities, the lower the detection limit of the sensor is, the more sensitive and reliable result the sensor can produce while monitoring the extreme low concentration of urea produced by the ammonium ions. Therefore, this sensor can be used to monitor natural water bodies and environments. This sensor has a detection limit lower than that of a regular sensor and is of better sensitivity. This sensor can more quickly detect the low concentrations of urea exists in the environment in the future and can monitor the blood and urine in human bodies. If this electrode can be fully developed in the future, it can bring significant contribution to the environmental protection and human body wellness. Keywords: Ammonia, Ammonium biosensor, Ammonium ion-selective electrod