A non-enzymatic electrochemical sensor based on nitrogen-doped mesoporous carbon@hydroxyl-functionalized ionic liquid composites modified electrode for the detection of fenitrothion

Abstract

The overuse of organophosphorus pesticides (OPs) results in severe environmental pollution and food safety issues. Fenitrothion (FNT) is a typical derivative of OPs, so rapid and sensitive detection of FNT plays an important role in environmental protection and public health. An FNT non-enzymatic electrochemical sensor based on nitrogen-doped mesoporous carbon@functionalized ionic liquid composites (N-CMK-3@IL) was constructed in this work. The surface topography and electrochemical properties of the sensor were investigated by scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), respectively. Because N-CMK-3@IL composites could improve the conductivity and increase the active surface area of the modified electrode, the sensor exhibited good electrocatalytic activity to FNT. Under the optimal experimental conditions, a good linear relationship for FNT was obtained in the range of 0.5–100 ng mL⁻¹, and the detection limit was 0.1 ng mL⁻¹ (S/N = 3). The sensor was successfully applied for the detection of FNT in vegetable samples.