A fumonisins immunosensor based on polyanilino-carbon nanotubes doped with palladium telluride quantum dots

摘要

An impedimetric immunosensor for fumonisins was developed based onpoly(2,5-dimethoxyaniline)-multi-wall carbon nanotubes doped with palladium telluridequantum dots onto a glassy carbon surface. The composite was assembled by a layer-by-layermethod to form a multilayer film of quantum dots (QDs) and poly(2,5-dimethoxyaniline)-multi-wall carbon nanotubes (PDMA-MWCNT). Preparation of the electrochemicalimmunosensor for fumonisins involved drop-coating of fumonisins antibody onto thecomposite modified glassy carbon electrode. The electrochemical impedance spectroscopyresponse of the FB1 immunosensor (GCE/PT-PDMA-MWCNT/anti-Fms-BSA) gave a linearrange of 7 to 49 ng L−1 and the corresponding sensitivity and detection limits were0.0162 kΩ L ng−1 and 0.46 pg L−1, respectively, hence the limit of detection of theGCE/PT-PDMA-MWCNT immunosensor for fumonisins in corn certified material wascalculated to be 0.014 and 0.011 ppm for FB1, and FB2 and FB3, respectively. These resultsare lower than those obtained by ELISA, a provisional maximum tolerable daily intake(PMTDI) for fumonisins (the sum of FB1, FB2, and FB3) established by the JointFAO/WHO expert committee on food additives and contaminants of 2 μg kg−1 and the maximum level recommended by the U.S. Food and Drug Administration (FDA) forprotection of human consumption (2–4 mg L−1).