Silver Nanoparticle-Decorated Carbon Fiber Microelectrode for Imidacloprid Insecticide Analysis

The electrocatalytic activity of silver towards imidacloprid reduction was demonstrated at both macro- and nano-scales. Coupled with the advantages of microscopic electrodes, this has led to the development of a highly-sensitive and selective electrochemical sensor for imidacloprid detection. This sensor utilizes silver nanoparticle-decorated carbon fiber microelectrodes (AgNPs/CF) fabricated through a single-step electrodeposition. Employing AgNPs/CF, the linear range, sensitivity, and limit of detection (3S B /m) were determined to be 0.0–0.40 mM, 2.98 × 10 −8 ± 0.10 × 10 −8 A mM −1 , and 60.4 nM, respectively. The sensor was successfully applied to detect imidacloprid directly in various water samples without the need for sample preparation, demonstrating ca. 100% recoveries. Moreover, the sensor was applied to analyze imidacloprid release from contaminated soil samples, revealing Langmuir characteristics of the desorption process.