FABRICATION OF NOVEL ELECTROCHEMICAL BIOSENSOR FOR FENITROTHION DETECTION USING G-C3N4@ZNO-NIO NANOHYBRID

Abstract

A widespread utilization of organophosphate pesticides in the agriculture sector has led to serious environmental and public health issues due to the toxicity and non-biodegradability. One of the most commonly used organophosphate pesticides, fenitrothion, can enter water, soil and food products causing serious health effects to people and ecosystems. So, it is highly needful to evolve a rapid, sensitive and cost-effective detection method for fenitrothion monitoring. In the present study, a nanocomposite of graphitic carbon nitride (g-C3N4) and zinc–nickel oxide (ZnO NiO) has been successfully fabricated to develop an electrochemical biosensor for sensitive detection of fenitrothion. Graphitic carbon nitride was synthesized by thermal polymerization of melamine and the zinc–nickel oxide nanostructures were synthesized by a hydrothermal synthesis method. The synthesized nanomaterials were further used to make a hybrid nanocomposite that exhibited improved conductivity, high surface area and better electrocatalytic activity. The fabricated nanocomposite was then coated on an indium tin oxide (ITO) electrode to fabricate an electrochemical biosensor. X-ray diffraction, field-emission scanning electron microscopy and Fourier transform infrared spectroscopy were used to characterize the synthesized materials structurally and morphologically. Cyclic voltammetry and differential pulse voltammetry were also used for the electrochemical studies. The developed biosensor was highly sensitive, rapid, highly selective and had a low detection limit for fenitrothion. The synergistic effect between g-C3N4 and Zn-Ni oxide was believed to be responsible for the improved sensing performance by providing efficient electron transfer and making a more active sensing.