An electrochemical immunosensing of electrochemically modified carbon cloth electrode based on functionalized gold nanoparticle-Prussian blue for the detection of aflatoxin B1 in vegetable oil industry

This study developed an electrochemical immunosensor for the detection of aflatoxin B1 (AFB1) in vegetable oil, based on an electrochemical modified carbon cloth (EMCC) electrode modified with a composite functional layer of cross-linked o-aminothiophenol functionalized AuNPs (o-ATP@AuNPs)/Prussian Blue (PB). The EMCC electrode substrate was prepared by modifying carbon cloth through electrochemical methods to increase its surface area, which allowed for the effective deposition of o-ATP@AuNPs/PB composite functional layer and improved the conductivity of the electrode material. The synergistic effect of o-ATP@AuNPs and PB significantly enhanced the sensitivity of the electrochemical sensor. Additionally, the AuS bond between L-Cysteine (L-Cys) and o-ATP@AuNPs improved the stability of the sensing interface. Under optimal conditions, the BSA/anti-AFB1/L-Cys/o-ATP@AuNPs/PB/EMCC sensor was able to detect AFB1 in the range of 0 to 20 ng mL⁻¹ using square wave voltammetry (SWV), with a detection limit of 0.015 ng mL⁻¹. The proposed sensor holds promise for future applications in the sensitive detection of AFB1 in vegetable oils.