Synthesis of cyclodextrin-reduced graphene oxide hybrid nanosheets for sensitivity enhanced electrochemical determination of diethylstilbestrol

► β-CD-RGO hybrid nanosheets were successfully prepared by using l-AA as the reducing agent under a mild condition. ► β-CD-RGO/GCE greatly enhanced the electrochemical response of diethylstilbestrol (DES). ► DES can be detected with wide linear range and a low detection limit. ► β-CD-RGO/GCE can be applied in real milk samples analysis with satisfactory results. β-Cyclodextrin functionalized reduced graphene oxide hybrid nanosheets (β-CD-RGO) were successfully prepared by using l-ascorbic acid (l-AA) as the reducing agent under a mild condition and used as enhanced material for sensitivity determination of diethylstilbestrol (DES). In 0.1M PBS (pH 7.0), the redox peak currents of DES increased significantly on β-CD-RGO modified glassy carbon electrode (β-CD-RGO/GCE), suggesting that the composite film not only shows excellent electronic properties of RGO sheets but also exhibits high supramolecular recognition capability of β-CD. The experimental conditions were optimized and the kinetic parameters were investigated. Under the optimal conditions, the reduction peak current of DES increased linearly with increasing the concentration in the range from 0.01 to 13μM with the detection limit of 4nM (S/N=3). The developed electrochemical sensor exhibited high selectivity, good stability and reproducibility, and also successfully determined DES in milk samples with satisfactory results.