Abstract

A new sensing layer composed of BSA templated Au-Pt bimetallic nanoclusters (Au-Pt BSA/GCE) and graphene nanoribbons (GNRs) was employed for the rapid, selective and sensitive determination of diazinon as an enzymeless electrochemical sensor. The UV-vis absorption spectroscopy, fluorescence spectroscopy, transmission electronic microscopy, X-ray diffraction and Fourier transform infrared techniques were used to investigate the size, morphology, and structure of the synthesized nanocomposite. Additionally, the electrochemical properties of the sensor were investigated by cyclic voltammetry, square wave anodic stripping voltammetry and electrochemical impedance spectroscopy. The results showed that Au-Pt BSA-GNRs/GCE significantly catalyzes the oxidation and reduction of diazinon during electrochemical detection. The linear ranges of diazinon were between 0.01-10.0 and 10.0-170 mu M, with a detection limit of 0.002 mu M. The selectivity, stability, and reproducibility of Au-Pt BSA-GNRs/GCE were studied, and obtained data indicates the great potential of the sensor as an alternative to enzyme inhibition-based biosensors for the determination of diazinon. The constructed electrode was employed for the determination of diazinon in some real samples with complex matrices such as soil, diverse water, fruit, and vegetables. The results indicate the excellent capability of the method for the detection of diazinon in real samples in comparison with the standard method.