Development of an electrochemical immunosensor for fumonisins detection in foods

An electrochemical affinity sensor for the determination of fumonisins mycotoxins (Fms) using monoclonal antibody modified screen-printed gold electrode with carbon counter and silver-silver chloride pseudo-reference electrode is reported in this work. A direct competitive enzyme-linked immunosorbent assay (ELISA) was initially developed, exhibiting a detection limit of 100 µg·L(-1 )for fumonisins. This was then transferred to the surface of a bare gold screen-printed electrode (SPGE) and detection was performed by chronoamperometry, monitoring the reaction of 3,3',5,5'-Tetramethylbenzidine dihydrochloride (TMB) and hydrogen peroxide (H(2)O(2)) catalysed by HRP at -100 mV potential vs. onboard Ag-AgCl pseudo-reference electrode. The immunosensor exhibited detection limit of 5 µg·L(-1) fumonisins with a dynamic range from 1 µg·L(-1)-1000 µg·L(-1). The sensor also performed well in extracted corn samples.