Portable Electrochemical Sensing Platform for Aflatoxin B1 Detection in Food Matrices

Aflatoxin B1 (AFB1) is one of the most hazardous foodborne toxins, posing a major risk to food safety and human health worldwide. Traditional detection techniques are often limited by lengthy procedures, high costs, and insufficient sensitivity for on-site applications. To overcome these challenges, we developed a portable, non-faradaic electrochemical impedance spectroscopy (EIS) platform designed for rapid and highly sensitive detection of AFB1 in overnight-soaked corn samples. The working electrode was modified with a semiconducting-gold composite layer, followed by DTSSP crosslinker chemistry and antibody immobilization, which provided enhanced surface activity and stable biofunctionalization. This configuration enabled fast detection within 5 minutes, achieving an impressive detection limit of 0.005 ng/mL and a wide dynamic range of 0.01–40.96 ng/mL. The sensor demonstrated excellent reproducibility, with intra- and inter-study %CV consistently below 20%. Validation against laboratory benchtop systems showed a strong correlation (Pearson r = 0.977). Diagnostic evaluation further confirmed its robustness, yielding 90.6% accuracy and an AUC of 0.83. These results highlight the combined benefits of nanocomposite surface engineering and non-faradaic EIS detection in achieving highly sensitive performance. Compact, user-friendly, and reliable, this sensing platform represents a promising solution for on-site toxin detection in food supply chains, thereby contributing to improved food safety monitoring and reduced public health risks associated with AFB1 exposure.