Zirconia electrodeposited on a self-assembled monolayer on a gold electrode for sensitive determination of parathion

A self-assembled monolayer (SAM) template was employed for the electrodeposition of zirconia nanoparticles (ZNPs) film on a gold electrode. The ZNPs film was highly stable and could selectively adsorb molecules containing phosphoric groups. Therefore, a sensor was developed for the determination of parathion based on the ZNPs electrodeposited on the SAM modified gold electrode. The electrochemistry of parathion on the present electrode was studied using cyclic voltammetry and square-wave voltammetry. A linear adsorptive stripping voltammetric response over the concentration range from 0.005 to 1.0 μg ml−1 (after a 2-min adsorption) was obtained under the optimized operational parameters of square wave voltammetry. The limit of detection was 0.8 ng ml−1 (S/N = 3). The ZNPs modified on SAM surface of gold electrode exhibits acceptable reproducibility (RSD 4.16%, n = 10) and a good stability. The electrode was applied to the determination of parathion in real samples, and satisfactory results were obtained.