Potassium Ion Sensor Based on Crown Ether Modified Silicon Nanowire Field-Effect Transistor

• Main Authors: Yu-Hsiu Yeh, 葉聿修
• Other Authors: 陳逸聰
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/53719165378170033653

碩士 === 臺灣大學 === 化學研究所 === 98 === We demonstrated that the fair signal processing procedure for comparing two signals collected from different devices is mapping the conductance signal to potential change, although this method was first published by Professor Zhou. We use trimethylsilane group modification to show that the primary source of signal induced by ion concentration is the equivalent capacitance result from ion concentration, but not non-specific ion coulomb interaction. After elucidating the source of ionic background interference, we further try to use various surface modifications for reducing ionic strength effect. The best performance surface modification we have tried shown little response when solution environment changes from 1X PBS to mouse plasma, which indicates the possibility of this method to be applied in bio-analysis. We applied the ionic strength control method in potassium detection, the results revealed that the significance of surface blocking group and the distinguishable selectivity between potassium and sodium. We also applied the oxide surface theory to device surface and adjusted the surface potential to its pHpzc, under this certain circumstances, ionic strength shown no effect, and crown ether based ion sensor show strong correlation between device signals and crown ether ion affinity.