A Simple and Efficient Electrochemical Sensor for Electrocatalytic Reduction of Nitrite Based on Poly(4-aminoacetanilide) Film Using Carbon Paste Electrode

In this study, the electrochemical reduction of nitrite was investigated on poly(4-aminoacetanilide) (PPAA) forming by cyclic voltammetry at the surface of carbon paste electrode. The electrochemical properties of the modified electrode have been studied by cyclic voltammetry and double potential step chronoamperometry. Results showed that in the optimum condition (pH = 0.00) the reduction of nitrite occurred at a potential about 667 mV more positive than that unmodified carbon paste electrode. This amount of electrocatalytic ability is high compared with other electrocatalysts. Using a chronoamperometric method, the catalytic rate constant (k) was calculated 8.4 x 10(4) cm(3) mol(-1) s(-1). Also, the electrocatalytic reduction peak currents was found to be linear with the nitrite concentration in the ranges of 5 x 10(-4) M to 2.5 x 10(-2) M and 2 x 10(-5) M to 7 x 10(-3) M with detection limits (2 sigma) were determined as 4.5 x 10(-4) M and 1 x 10(-5) M by cyclic voltammetry (CV) and hydrodynamic amperometry methods respectively. Recovery experiments exhibit the satisfactory results.