Glocuse detection with a commercial MOSFET using ZnO nanowires extended gate

Zinc oxide (ZnO) nanowires were grown on a silver (Ag) wire with a diameter of approximately 250 $mu$m and used in an electrochemical sensor. The enzyme glucose oxidase (GOD) was immobilized on the ZnO nanowires and the silver wire was connected directly to the gate of a MOSFET. Upon exposure to glucose (1-100 $mu$M) the electrochemical response from the glucose oxidase induced a stable measurable voltage change on the gate leading to a strong modulation of the current through the MOSFET. For a sensor with uniform ZnO nanowires functionalized with GOD a fast response time of less than 100 ms, was demonstrated. The effect of the uniformity of the ZnO nanowires on the sensing property was also investigated. The extended gate arrangement facilitated glucose detection in small sample volumes and made it possible to demonstrate the present sensor concept using a standard low threshold MOSFET. The extended gate MOSFET sensor approach demonstrates the possibility and potential of the use of nano-structures coupled to standard electronic components for biosensing applications.©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Syed M. Usman Ali, Omer Nour, Magnus Willander and Bengt Danielsson, Glocuse detection with a commercial MOSFET using ZnO nanowires extended gate, 2009, IEEE Transaction on Nanotechnology, (8), 6, 678-683.http://dx.doi.org/10.1109/TNANO.2009.201995