A yolk shell Fe3O4 @PA-Ni@Pd/Chitosan nanocomposite -modified carbon ionic liquid electrode as a new sensor for the sensitive determination of fluconazole in pharmaceutical preparations and biological fluids

In this study, a versatile method was used to synthesize Ni@Pd core-shell nanoparticles, immobilized on Fe3O4@ polyaniline yolk-shell composites (Fe3O4@PA). The constructed Fe3O4@PA-Ni@Pd composite and Chitosan were utilized for the modification of carbon ionic liquid electrode (CIIE) in high sensitive determination of fluconazole (FLU). A carbon ionic liquid electrode constructed using graphite powder mixed with 1-Butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) in place of paraffin as the binder showed strong electrocatalytic activity to the direct oxidation of Fluconazole. The properties of the electrode surface were characterized by scanning electron microscope (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Thermal gravimetric analysis (TGA), X-Ray Photo-Emission Electron Microscopy (XPES), Electrochemical Impedance Spectroscopy (EIS), Chronocoulometry (CC) and chronoamperometery (CA) techniques. The recommended quadratic model obtained from the full factorial Box-Behnken design (BBD) was in accordance with the experimental data in an acceptable range. The response was studied in relation to such critical factors as pH. accumulation time, concentration of nanoparticles, and scan rate. The peak currents were proportional to fluconazole concentration in a linear range from 0.01 to 400 mu mol L-1, with a detection limit of 3.5 nmol L-1. Then the constructed sensor was successfully used for the quantification of fluconazole in serum, urine, and tablets. (C) 2018 Published by Elsevier B.V.