多晶矽奈米線生物分子感測元件之研發

Abstract

近年來在醫學疾病的檢測，開始針對分子標誌進行診斷。治療方式也開始對於引發疾病的特定分子做特定的治療。因此我需要具有準確且快速檢測生物分子的工具或方法，期望達到疾病早期發現、早期治療的目標。矽奈米線電晶體元件，近年來已被證實可以做為高靈敏度的生物分子感測器。可以對於不同的生物分子進行高靈敏度、即時、快速、準確的感測。 在本論文中我們發展出一種簡單而快速的方法製備多晶矽奈米線薄膜電晶體元件。並將此元件應用於生化感測方面。將多晶矽奈米線通道曝露在不同酸鹼值的溶液中，並量測元件臨界電壓及電流的變化。我們利用卵白素及生物素的專一性親和力，來進行生物分子感測的實驗。將帶有螢光分子的卵白素固定在多晶矽表面，並使用螢光顯微鏡觀察其螢光圖形。將多晶矽奈米線曝露在不同濃度的蛋白質溶液環境中，偵測多晶矽奈米線元件電性的變化。我們感測的目標蛋白質為卵白素，感測的範圍為10-12莫爾濃度至10-8莫爾濃度。

In recent years, the medical diagnostics and diagnostic judgments begin using molecular markers approach, and highly specific therapies aimed at molecular targets. Therefore we need high-throughput methods for rapid detection of biological molecules. Expect to achieve early detection of disease, early treatment goals. The silicon nanowire transistor devices had been proven as high sensitivity biomolecular sensors. The silicon nanowire devices can detect biomolecules with high sensitivity, real-time, fast and accurate. In this work, we fabricated poly-silicon nanowire thin-film transistors with simple and fast method. The shifts of threshold voltage and the changes of current were detected by exposing the poly-silicon nanowires to buffer solutions of different pH value. A biomolecular detection experiment was set up using the specific binding of biotin to streptavidin/avidin. First we immobilized protein with fluorescent molecules on the poly-silicon surface, and used fluorescent microscope to observe the fluorescent pattern. We measured the electronic properties of the poly-silicon nanowire thin-film transistors in different concentration streptavidin/avidin. Specific electric changes were observed for streptavidin and avidin sensing when the poly-silicon nanowire surface was modified with biotin and streptavidin at pM to dozens nM range could be distinguished.