▎ 摘　　要

Results of this paper related to fabrication of a simple, reproducible, stable and sensitive electrochemical sensing platform of progesterone (P4) based on graphene quantum dots (GQDs) nanocomposite. GQDs, Fe3O4 nanoparticles and functionalized multi-walled carbon nanotubes (f-MWCNTs) modified glassy carbon electrode (Fe3O4@GQD/f-MWCNTs/GCE) were constructed and the electrocatalytic properties of the modified electrode toward the oxidation of P4 were analyzed. GQDs with the size of about 15 nm were prepared by a facile and low expense bottom-up method by carbonization of citric acid and dispersing the carbonized products into alkaline solution. The characterization of the sensor was studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and voltammetry techniques. Electrochemical studies suggested that as-prepared sensor revealed some advantages in terms of high effective surface area, more reactive sites and excellent electrochemical catalytic activity toward the oxidation of P4. After optimization of analytical conditions, the peak currents for P4 were found to vary linearly with its concentrations in the wide range of 0.01-0.5 and 0.5-3.0 mu M. The estimated detection limit and sensitivity of the electrode were 2.18 nM and 16.84 mu A mu M-1, respectively. This sensor exhibited excellent stability, selectivity, sensitivity and reproducibility and could be successfully applied for determination of P4 in human serum samples and pharmaceutical products with excellent recoveries and without the interferences of coexisting substances. (C) 2016 Elsevier B.V. All rights reserved.