Ultra-sensitivity glucose sensor based on field emitters

Abstract

A new glucose sensor based on field emitter of ZnO nanorod arrays (ZNA) was fabricated. This new type of ZNA field emitter-based sensor shows high sensitivity with experimental limit of detection of 1 nM glucose solution and a detection range from 1 nM to 50 μM in air at room temperature, which is lower than that of glucose sensors based on surface plasmon resonance spectroscopy, fluorescence signal transmission, and electrochemical signal transduction. The new glucose sensor provides a key technique for promising consuming application in biological system for detecting low levels of glucose on single cells or bacterial cultures.

Keywords: Field emitter; Glucose sensor; High sensitivity; ZnO nanorod arrays.

Figure 1

SEM images of ZNA:aTop view,bcross-section view

Figure 2

Field emission J–Ecurvesathe ZNA immersing in the glucose concentration from 1 to 500 nM in 6 mM PBS buffer solution and 10 U μL⁻¹glucose oxidase with a pH value of 5.8.bThe control experiments, the ZNA immersing 6 mM PBS buffer solution, 1 mM glucose in 6 mM PBS buffer solution, 10 U μL⁻¹glucose oxidase in 6 mM PBS buffer solution, respectively, with a pH value of 5.8

Figure 3

aPlot of change resistance (R) as a function of concentrations (M) from 1 nM to 50 μM in 6 mM PBS buffer solution and 10 U μL⁻¹glucose oxidase with a pH value of 5.8.bDependence relation between response sensitivity and glucose concentrations

Figure 4

A schematic illustration of the ZNA field emitter-based glucose sensor operating principles