Sensitive and Selective Electrochemical Detection of Epirubicin as Anticancer Drug Based on Nickel Ferrite Decorated with Gold Nanoparticles

The accurate and precise monitoring of epirubicin (EPR), one of the most widely used anticancer drugs, is significant for human and environmental health. In this context, we developed a highly sensitive electrochemical electrode for EPR detection based on nickel ferrite decorated with gold nanoparticles (Au@NiFe2O4) on the screen-printed electrode (SPE). Various spectral characteristic methods such as Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-Vis), energy-dispersive X-ray spectroscopy (EDX) and electrochemical impedance spectroscopy (EIS) were used to investigate the surface morphology and structure of the synthesized Au@NiFe2O4 nanocomposite. The novel decorated electrode exhibited a high electrocatalytic activity toward the electrooxidation of EPR, and a nanomolar limit of detection (5.3 nM) was estimated using differential pulse voltammetry (DPV) with linear concentration ranges from 0.01 to 0.7 and 0.7 to 3.6 µM. The stability, selectivity, repeatability reproducibility and reusability, with a very low electrode response detection limit, make it very appropriate for determining trace amounts of EPR in pharmaceutical and clinical preparations.

Improvement of Electrochemical Performance of ZnCo2O4@Co9S8 Nanosheets for Supercapacitors

ZnCo2O4@Co9S8 nanostructures were grown on the surface of Ni foam by facile hydrothermal method and subsequent thermal treatment process, thus increasing the active site on the surface of the material. After vulcanization treatment, the performance of the composite material has been significantly improved the product has a higher specific capacitance of 1018.2 F g−1 at 4 A g−1. This work demonstrates that ZnCo2O4@Co9S8 nanostructures are highly desirable for application as advanced electrochemical electrode materials.

Computational Study of Graphene–Polypyrrole Composite Electrical Conductivity

In this study, the electrical properties of graphene–polypyrrole (graphene-PPy) nanocomposites were thoroughly investigated. A numerical model, based on the Simmons and McCullough equations, in conjunction with the Monte Carlo simulation approach, was developed and used to analyze the effects of the thickness of the PPy, aspect ratio diameter of graphene nanorods, and graphene intrinsic conductivity on the transport of electrons in graphene–PPy–graphene regions. The tunneling resistance is a critical factor determining the transport of electrons in composite devices. The junction capacitance of the composite was predicted. A composite with a large insulation thickness led to a poor electrochemical electrode. The dependence of the electrical conductivity of the composite on the volume fraction of the filler was studied. The results of the developed model are consistent with the percolation theory and measurement results reported in literature. The formulations presented in this study can be used for optimization, prediction, and design of polymer composite electrical properties.

Fabrication of flexible wearable electrodes based on carbon nanotubes/nickel/nickelous hydroxide ternary composites by a facile single side printing technology

A new strategy of materials design is performed to prepare high performance flexible electrochemical electrode. Carbon nanotubes (CNTs) and nickel/nickelous hydroxide (Ni/Ni(OH)2) are compounded through chemical plating method and hydrothermal...