Ultra-Sensitive Determination of Fenitrothion Pesticide in Orange Juice by Gold-Printed Electrode Modified with AgNP/Carbon Dot/MWCNT Nanoarchitecture Employing Electrochemical Impedance Spectroscopy

This work describes the synthesis, characterization, and electrochemical application of innovative AgNP/carbon dot/MWCNT nanoarchitecture. Silver nanoparticles (AgNPs) have been obtained by directly reducing silver nitrate salt in carbon dot/MWCNT alcoholic solution. UV–vis spectroscopy, HR-TEM, XPS, and electrochemical techniques have characterized this nanoarchitecture. The AgNP/carbon dot/MWCNT nanoarchitecture has been dispersed on a gold-printed electrode surface, showing excellent electrocatalytic activity for fenitrothion determination in acetate buffer, pH 4.5, by impedance electrochemistry spectroscopy with a detection limit of 0.48 nmol L⁻¹. The fenitrothion pesticide detection was also performed in orange juice and did not suffer significant interference from other pesticides.