矽奈米線元件於細胞釋放腺嘌呤核甘三磷酸之感測研究

Abstract

本論文運用矽奈米線場效電晶體做為高靈敏度的生物感測器，用來偵測label-free 的生物小分子；經過參雜Boron(硼)的矽奈米線有很高的靈敏度，所以運用來做生物感測器，矽奈米線會依據外圍的分子帶電荷的不同而造成其電性的改變，可以藉由觀察矽奈米線場效電晶體的電導(conductance)的變化來作為分子的偵測。Abl tyrosine kinase是一種磷酸轉移酶，在慢性骨髓性白血病中的病人會有突變，在本實驗中將Abl tyrosine kinase用共價鍵的修飾在矽奈米線的表面上，因為Abl tyrosine kinase對ATP有很好的親和力，所以可以用來偵測細胞的「能量通貨」ATP。實驗中利用矽奈米線場效電晶體做ATP的即時偵測，在低離子濃度的緩衝液中，可以量測到濃度1 pM的ATP，在高離子濃度的緩衝溶液中，也可以量測到濃度1 nM的ATP。除此之外，在本論文中還進一步直接測到由HeLa cell經電極結構刺激後所釋放的ATP，證明矽奈米線場效電晶體可以即時偵測到生物體所釋放的label-free小分子。

This study utilized ultrahigh sensitivity label-free silicon nanowire field-effect transistors (SiNW FETs) to detect biological small molecule. Boron-doped silicon nanowires were adopted due to the properties of highly sensitive, real-time electrical response to charged biological and chemical species. Abl, which is a protein tyrosine kinase whose constitutive activity is responsible for chronic myelogenous leukemia, was covalently linked to the surfaces of silicon nanowires for the detection of Adenosine triphosphate (ATP), the energy currency of cells. A real-time time-dependent measurement of conductance of SiNW FETs showing that detection of ATP down to a picomolar concentration is achievable. In high ion strength buffer, due to shorter Debye screening effect, the detection limit of SiNW FETs for ATP was at nanomolar range. Furthermore, this investigation applied the interdigited electrodes to stimulate the HeLa cell to release ATP and SiNW FETs were adopted for real-time detection of ATP.