Development of a cellular biosensor for the detection of aflatoxin B1, based on the interaction of membrane engineered Vero cells with anti-AFB1 antibodies on the surface of gold nanoparticle screen printed electrodes

• Aflatoxin B1 cytotoxicity on Vero cells was assessed.
• Cell modification with the anti-Aflatoxin B1 antibody through membrane engineering.
• Cell culture on Screen Printed Electrodes surface.
• Development of a mammalian cell biosensor for aflatoxin B1 detection.

The development of methods for the detection of aflatoxin B1 (AFB1) in foods is a very important practice for ensuring food quality and safety. Most tests of AFB1 are still conducted with conventional methods (i.e. antibody-based ELISA tests, high performance liquid chromatography – HPLC); however biosensor methods are being developed to date as screening tools for field analysis. Compared to immunology/ELISA-like tests or chromatography methods, biosensors are able to provide rapid, sensitive, robust and cost effective quantitative methods for on-site testing. In this work we propose a cellular biosensor based on Vero cells, membrane engineered with anti-AFB1 antibody as the biological recognition element reacting with AFB1 molecules on gold nanoparticle/screen printed electrodes (SPEs) (three electrode system). In order to culture the cells on the SPEs surfaces the working electrodes were coated with poly-l-lysine to facilitate cell adhesion. The SPEs were connected to a potentiostat device through a transducer and chronoamperometric (CA) and cyclic voltammetric (CV) measurements were performed. Quantitative results obtained using the cellular biosensor method for AFB1 were compared to those obtained using the HPLC method in pistachio samples spiked with AFB1. The method displayed good sensitivity (r2 = 0.87) and detection limit (0.5 ng/mL).