A molecularly imprinted electrochemical sensor co-modified with palladium-metallene and graphene nanoribbons for the detection of zearalenone.

A composite modified electrochemical sensor was developed based on molecular imprinting technology for zearalenone (ZLE) detection. The sensor was fabricated on a glassy carbon electrode (GCE) by first electrochemically reducing and depositing graphene oxide nanoribbons (rGNR) to form a highly conductive three-dimensional network. Subsequently, palladium-metallene (Pd-Me) was coated to enhance the electrochemical response. Finally, acrylamide molecularly imprinted polymer (AMIP) was polymerized in situ under infrared light to impart specific recognition capability. Performance tests demonstrated that the fabricated sensor (AMIP/Pd-Me/rGNR/GCE) exhibited a linear response to ZLE in the range of 1.0 - 1000 ng/mL, with a detection limit of 0.33 ng/mL (S/N = 3). The sensor also showed good selectivity, repeatability (signal attenuation ≤ 5.63% after five consecutive detections), reproducibility (relative standard deviation, RSD = 2.62%), and storage stability (96.85% signal retention after two weeks at 4 °C). When applied to actual samples (grain flour, soybean flour, and corn flour), the spiked recoveries ranged from 97.26% to 104.09%, with RSD below 4.58%. These results confirm that the sensor can achieve precise quantitative detection of ZLE in complex food matrices. The sensor preparation process, which combines electro-polymerization and coating, is characterized by simple operation, strong film formation, low cost, and ease of miniaturization, offering a promising new approach for the rapid determination of mycotoxins in food safety.