Rapid and Sensitive Determination of Dinotefuran Residue Based on Electrochemical Enhancement of β-cyclodextrin-Graphene Composite

A rapid method for sensitive voltammetric determination of dinotefuran residue was reported. The proposed method was based on the electrocatalytic reduction of dinotefuran on beta-cyclodextrin-graphene composite modified glassy carbon electrode (beta-CD-rGO/GCE), giving rise to a higher reduction signal to dinotefuran relative to the bare (GCE) and graphene modified electrode (rGO/GCE). Moreover, a further signal enhancement was observed when the modified electrode incubated in solution at low temperature (0 degrees C) for a short time. The reduction mechanism and binding affinity were also discussed. The external standard calibration curve was obtained from linear sweep voltammetry in the range of 0.5 to 16.0 mu M with a detection limit of 0.10 mu M. In addition to optimization of pretreatment, this electrochemical method has been applied to the dinotefuran residue determination in millet samples with the detection limit of 0.01 mg kg(-1) and compared with an high performance liquid chromatography method. The proposed electrode and analysis methods were proven to be sensitive, accurate and rapid under the used conditions.