Graphene oxide encapsulated 3D porous chalcopyrite (CuFeS₂) nanocomposite as an emerging electrocatalyst for agro-hazardous (methyl paraoxon) detection in vegetables

Methyl paraoxon (MOX) is a highly toxic organophosphate pesticide. It is recently reported that, MOX can enter the human body through ingestion, inhalation, or by dermal penetration. Due to its high non-degradability, it can bind to the tissues of fruits and vegetables. When it is consumed, it can imposes sub-chronic and chronic diseases, by the inhibition of acetylcholinesterase in human metabolism. Therefore, for the first time, we reported a detection of non-enzymatic electrochemical sensor based on 3D porous phase graphene oxide sheets encapsulated chalcopyrite (GOS@CuFeS₂) nanocomposite. Hence, the development of reliable sensors for the real-time detection of pesticides is imperative to overcome practical limitations encountered in conventional methodologies. As synthesized GOS@CuFeS₂ nanocomposite film screen-printed carbon modified electrode (SPCE) displays excellent electrocatalytic ability towards MOX. Under optimized working conditions, the modified electrode provides linear response range from 0.073 to 801.5 μM. The detection limit was obtained as 4.5 nM. The sensor displayed outstanding sensitivity as 17.97 μA μM⁻¹ cm⁻². This composite could be a promising electrode modifier for electrocatalysis. Finally, the GOS@CuFeS₂ nanocomposite modified electrode shows greater real-time practicality in vegetable real samples. The obtained moral parameters from the developed method were compared with the authenticated HPLC results.