Highly sensitive electrochemical sensor based on pyrrolidinium ionic liquid modified ordered mesoporous carbon paste electrode for determination of carbendazim

Abstract

A simple, highly sensitive electrochemical sensor based on a pyrrolidinium ionic liquid (PIL) modified ordered mesoporous carbon (OMC) paste electrode (PIL/OMCPE) was developed for the determination of carbendazim by differential pulse voltammetry. The structure of the synthesized OMC was characterized by transmission electron microscopy. The electrochemical characteristics of the modified electrodes were investigated using [Fe(CN)₆]^3−/4− as the electrochemical probe. Compared with other electrodes, the PIL/OMCPE exhibited a larger electrode surface and a faster electron-transfer rate. The electrochemical behavior of carbendazim at the modified electrode was investigated by cyclic voltammetry. The PIL/OMCPE exhibited good performance for the electrochemical oxidation of carbendazim. The peak current of carbendazim at the PIL/OMCPE significantly increased in comparison with those at the bare carbon paste electrode (CPE), OMCPE, and PIL modified CPE. Under optimal conditions, the relationship between the carbendazim concentration and peak current was studied, and the developed PIL/OMCPE sensor exhibited good linearity in a wide range from 1.25 to 800 μg L⁻¹. The limit of detection was estimated to be 0.500 μg L⁻¹ (signal-to-noise ratio = 3). The proposed sensor was successfully applied for the determination of carbendazim in sugarcane samples with satisfactory results.