Electrochemical evaluation of fenitrothion organophosphate pesticide in food samples: Novel tetra trifluoromethyl carboxamide zinc (II) macrocyclic complex composite with multiwalled carbon nanotubes

This study presents the development of a groundbreaking electrochemical sensor for detecting fenitrothion (FNT) using a multi-walled carbon nanotubes (MWCNTs) and a newly synthesized zinc (II) tetra trifluoromethyl carboxamide phthalocyanine (ZnTFMPCAPc). The ZnTFMPCAPc was synthesized concluding a two-step mechanical and magnetic stirring method, and the ensuing ZnTFMPCAPc@MWCNTs underwent comprehensive characterization employing X-ray diffraction (XRD), Ultraviolet visible spectroscopy (UV–Vis), mass spectrum, Fourier transform infrared spectroscopy (FT-IR), Thermo-gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Mass, Raman spectra, Transmission Electron Microscopy (TEM) and scanning electron microscope (SEM). Cyclic voltammetry (CV) analysis demonstrated a remarkable seven-fold improvement in electrochemical signals with ZnTFMPCAPc@MWCNTs on modified glassy carbon electrode (GCE) compared to a bare and modified GCE. The correlation between peak current and FNT concentration (in the range of 10–310 μmol) was established. The estimated limits of detection (LOD) and quantification (LOQ) were determined to be 1.358 nmol and 4.075 nmol respectively. The ZnTFMPCAPc@MWCNTs/GCE sensor was successfully evaluated by quantifying FNT in tomatoes, grapes, paddy grains, and potato extracts, resulting in satisfactory results. Detecting fenitrothion is crucial due to its widespread use as a pesticide, which can result in environmental contamination and pose health risks. Regular monitoring is essential for protecting food and water supplies, preserving ecosystems, and ensuring compliance with regulations to prevent long-term environmental damage.