Nano-composite ZrO2/Au film electrode for voltammetric detection of parathion

This work describes the fabrication of ZrO2/Au nano-composite films and its application for voltammetric detection of organophosphate pesticides. The nano-composite ZrO2/Au film was prepared through a combination of sol–gel procedure and electroless plating that can be carried out in a general chemistry lab with no need for special facilities and reagents. The sensing performance of the ZrO2/Au nano-composite film electrode toward parathion was studied with square wave voltammetry. The nano-ZrO2 showed a strong affinity toward the phosphate group on parathion molecules, which provides sensitivity and selectivity of the sensing film. A linear relationship was obtained between the peak currents and the concentration of parathion, with a detection limit for standard samples of 3 ng/ml. In addition, interference studies showed that structurally similar compounds without phosphate groups would not interfere with the response toward parathion of the film electrode.