Figure 2

Field emission J–Ecurves a the 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.b The 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