Accurate and early diagnosis of zearalenone (ZEN) is particularly significant to the food safety. Herein, we propose an ionic liquid assisted self-assembly molecular imprinting strategy for ZEN based on ionic liquid functionalized boron-doped ordered mesoporous carbon -gold nanoparticles composite (BOMC-IL-Au NPs). During the composite synthesis, increased well-dispersed and uniform Au NPs are deposited on the surface of IL modified BOMC, due to the strong electrostatic interaction between AuCl4- and positively charged IL. For molecular imprinting, the BOMC-IL-Au NPs/GCE is immersed into p-aminothiophenol (p-ATP) solution and template solution in turn. Thus, the mercapto group contained p-ATP self-assembles on the Au NPs. Subsequently, the template molecules self-assemble onto the composite to form dense template layer, because of the hydrophobic interaction, π-π and hydrogen bond between template and IL/or p-ATP. After electropolymerization, the template layer is embedded into the p-ATP polymer membrane and produces lots of imprinting sites. Hence, the obtained sensor exhibits high sensitivity and selectivity. Under the optimal conditions, zearalenone can be quantified from 5 × 10-4 to 1 ng mL-1 with the low detection limit of 1 × 10-4 ng mL-1, by using [Fe(CN)6]3-/4- probe and square wave voltammetry. This strategy can also be employed to construct sensors for the detection of other substances.
Keywords: Electrochemical sensor; Ionic liquid; Molecularly imprinted polymer; Mycotoxin; P-aminothiophenol.
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