Non-Enzymatic Electrochemical Sensors Based on Conducting Polymer Hydrogels for Ultrasensitive Carbaryl Pesticide Detection

Abstract

Pesticides play a key role in agricultural development, but pesticide residues do great harm to human health and environmental safety. Therefore, it is urgent to design a rapid and accurate pesticide monitoring method. Herein, a sensitive, label-free and non-enzymatic electrochemical sensor based on conducting polymer hydrogels, was constructed for the detection of carbaryl in aqueous solution. In this work, conducting polymer hydrogels were electrochemically prepared onto glassy carbon electrode by electrochemical copolymerization of polyaniline (PANI) and hyaluronic acid (HA). Interestingly, PANI/HA hydrogel with multiple porous microstructure and high active specific area demonstrated excellent hydrophilic and electrochemical properties, leading to the strong affinity to carbaryl pesticide. A non-enzymatic electrochemical sensor based on PANI/HA nanocomposite exhibited a linear response of 0.01–1 ng ml−1 for carbaryl, and the detection limit was 0.0034 ng ml−1. The PANI/HA modified electrode was used to determine carbaryl in the fruit samples, which showed efficient sensing ability. Therefore, the method can be popularized in the field of agricultural safety and environmental monitoring, and provides a promising avenue for the detection of pesticide residues in real samples.