An innovative biosensing approach for Aflatoxin B1 detection via electrical impedance measurement

Abstract

Aflatoxin B1 (AFB₁) contamination poses a significant threat to food safety and public health, creating an urgent need for reliable and effective detection methods. This study presents a fast and sensitive biosensor for detecting AFB₁ in complex food samples. Scanning Electron Microscopy (SEM) shows the current functionalization of tungsten wires with antibodies and multi-walled carbon nanotubes (MWCNTs). The surface morphological changes are easily visible as they give rise to a roughened, textured surface that provides a greater active area, since the surface used for hydrogen evolution. Results from Differential Scanning Calorimetry (DSC) show that the enthalpy changes associated with antibody AFB₁ interactions are greater at higher AFB₁ concentrations, indicative of higher affinities of binding interactions. Differential scanning calorimetry (DSC) thermograms display clear endothermic peaks corresponding to different levels of AFB₁, providing information about the melting point as well as the stability and binding characteristics of the antibody complex. The biosensor achieves a broad detection range (0.1 ppb to 30 ppb), with charge transfer resistance decreasing from 1.5 Ω·cm² to 0.5 Ω·cm² as AFB₁ concentration increases. Using Electrical Impedance Spectroscopy (EIS) and advanced nanomaterials, this biosensor enables real-time monitoring of molecular interactions. By addressing the limitations of traditional detection methods, it offers a practical solution for enhancing food safety and preventing AFB1 contamination.