(A) Chronoamperometric responses of Au
electrode/cerium oxide upon
addition of different H2O2 concentrations. Applied
potential: −0.5 V. (B) Logarithmic relationship between the
concentrations of H2O2 (0.1, 0.5, 10, 100, 1000,
2000, and 20 000 μM). (C) Interference studies of cerium
oxide-based lab-on-a-chip device on addition of 1 mM UA, DA, AA, GLU,
GSH and 0.2 mM H2O2. (D) Chronoamperometric
responses of Au electrode/cerium oxide for the reduction of H2O2 released from 106 PC 12 cells in
1 mL of 1 × PBS (pH = 7.4): (a) PC12 cells, (b) AA (4 μM),
and (c) PC12 cells upon injection of 4 μM AA.