Electrochemical Impedimetric Sensor for Carbofuran Based on Screen-Printed Carbon Electrode Modified with Electrosynthesized Molecularly Imprinted Polypyrrole
摘要
Carbamate pesticides are widely used to improve agricultural production; however, their widespread application may leave residues in food, posing a severe threat to human health. In this study, an impedimetric sensor was developed for carbofuran (CBF), a common carbamate pesticide. The CBF sensor was based on a screen-printed carbon electrode modified with molecularly imprinted polypyrrole (MIPPy). MIPPy was deposited on the electrode through electropolymerization of pyrrole using cyclic voltammetry in the presence of CBF. Electrochemical impedance spectroscopy (EIS) was employed as the transduction principle for detecting CBF in aqueous solutions. The electropolymerization and measurement parameters affected the sensor response and were optimized. The sensor response was linear over a concentration range of 0.01 to 0.3 ppm CBF, with a Pearson coefficient of 0.992. The sensor exhibited good reproducibility and accuracy. The sensor was applied successfully in the determination of CBF in vegetable samples and validated through comparison with HPLC results.