An ELIME-array for detection of aflatoxin B1 in corn samples

The aim of the present work was the development of an ELIME-array to achieve simple and rapid detection of AFB1 in corn samples. The system is based on an indirect competitive ELISA format using magnetic beads as immobilisation support and eight magnetised screen-printed electrodes as electrochemical transducers. After an optimisation study, a corn sample treatment, employing an extraction in acetonitrile/water followed by a clean-up step and solvent evaporation, was selected. For the construction of the calibration curve, which was used to evaluate both evaluation of the matrix effect on the performances of the ELIME-array and for the analysis of Certified Reference Materials (CRMs), standard solutions of AFB1 were added to blank dried corn extracts reconstituted in PBS. The detection limit and the sensitivity of the assay were calculated to be 0.6 ng mL−1 and 1.5 ng mL−1, respectively. Precision (11–26%) and recovery (95–114%) data of the ELIME-array, determined by analysing four CRMs, have shown that the proposed system appears suitable as a screening tool for the analysis of AFB1 in corn samples