Nanomaterial-modified nanochannels electrochemical sensors for sensitive detection of zearalenone mycotoxin

This study presents the development of an electrochemical sensor based on nanochannels for the sensitive detection of the fungal toxin zearalenone (ZEN). The sensor incorporates gold nanoparticles (AuNPs) and multi-walled carbon nanotubes (cMWCNTs) onto anodic aluminum oxide (AAO), with nickel oxide (NiO) modification on the reverse side of the AAO, thereby forming a NiO-AAO@AuNPs-cMWCNTs/SPCE electrode system. The NiO modification facilitates the initial oxidation of ZEN, resulting in the generation of distinctive electrochemical oxidation peaks. To investigate the reaction mechanism of ZEN oxidation, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were employed. In the concentration range of 1 ~ 40 μg/mL, the sensor showed a clear linear correlation between ZEN concentration and the impedance response, expressed by the regression equation: R EIS (Ω)  = 40.8 + 2.7 C ZEN (μg/mL) (R 2  = 0.997, n = 3). The limit of detection (LOD) was determined to be 0.1 μg/mL. This nanochannel-based electrochemical platform provides a reliable and efficient strategy for ZEN detection, demonstrating the potential of nanostructured materials in food safety monitoring.