以結合微流道之銦鎵鋅氧化物薄膜電晶體偵測蛋白質與配體之反應行為

Abstract

論文中包含了兩個部分。首先是將薄膜電晶體應用於血清蛋白的偵測，其次是其在偵測蛋白質與配體之間的反應行為。 生物分子的偵測是當今熱門的研究。我們設計的蛋白質感測器結合了微流道系統。當待測物經由微流道擴散到金感測板時，會造成薄膜電晶體電流瞬間增加。不同的流道長度或是蛋白質濃度，都會影響電流變化的時間以及感應電荷的數量。而這些結果又可以經由理論關係式相互推導，因而達到偵測與量化的目的。我們的設計可以得到電性方面的資訊（蛋白質帶電量），並且同時可以得到流體的訊息（和蛋白質的尺寸大小及質量相關），是一個非常簡易卻又方便迅速的蛋白質感測器。 另外，蛋白質與配體間的交互作用一直是世界各大藥廠相當關切的議題。我們首先用薄膜電晶體感測器偵測蛋白質與配體分別的訊號，並給出一個估算式以預估量測未知擴散係數的生物分子時適合的調配濃度。我們進行螢光染色的影像拍攝以驗證先前純粹電性量測的結果。最後我們將配體引入蛋白質溶液並量測其電性反應，以探究兩者之間的反應行為。

There are two parts in this thesis. First of all, a TFT-based protein sensor with a microfluidic channel is designed to detect and quantify the bio-molecules. Secondly, the TFT sensor is further applied to detect the protein-ligand interaction between MDH and NADH. We demonstrate a TFT-based protein sensor combined with microfluidic channel. Due to the concentration gradient in solution, the analyte diffuses to the sensing pad through the microfluidic channel and causes a drain current increment. With various microfluidic channel lengths or different concentrations of IgG antibody, the results of response (diffusion) time and the amount of induced charges are quite distinguishable. All results following some theoretical relations. Thus, the unknown concentrations of IgG antibody can be obtained. Our design can acquire not only electrical information (the charges carried by the bio-molecules) but also fluidic information (diffusion time which is related to the size and weight of the bio-molecules). We next examine the diffusion and electrical signals of protein, ligand, and protein-ligand interaction. They were first measured separately to obtain information that would be referenced for later experiment. An estimation equation is provided for new analyte with unknown diffusion coefficient, and is verified in our experiment to have accurate evaluation of diffusion time. We also did the fluorescent snapshots to gain a visual picture of the diffusion scheme aside from electrical measurement. Finally, protein-ligand interaction is detected by our TFT sensor.