Cyclodextrin-graphene hybrid nanosheets as enhanced sensing platform for ultrasensitive determination of carbendazim

In this paper, cyclodextrin-graphene hybrid nanosheets (CD-GNs) for the first time have been used as an enhanced material for ultrasensitive detection of carbendazim by electrochemistry method. The peak currents of carbendazim on the GNs modified glassy carbon electrode (GNs/GCE) and the CD-GNs/GCE are increased by 11.7 and 82.0 folds compared to the bare GCE, respectively. This indicates the nanocomposite film not only shows the excellent electrical properties of GNs but also exhibits high supramolecular recognition capability of CDs. At the CD-GNs/GCE, the peak currents increase linearly with the concentration of carbendazim in the range of 5 nM-0.45 μM. The detection limit of carbendazim reached to 2 nM on the basis of the signal-to-noise characteristics (S/N=3) and the recoveries were between 98.9% and 104.5%. The developed electrochemical sensor exhibited good stability and reproducibility for the detection of carbendazim. And the CD-GNs based electrochemical sensor was also successfully demonstrated for the detection of carbendazim in water sample with satisfactory results. Furthermore, this simple sensing platform can in principle be extended to the detection of other benzimidazole fungicide which can form host-guest complexes with cyclodextrin.