Palladium nanoparticles immobilized on polymer-functionalized magnetic nanoparticles for the determination of hydrogen peroxide

Abstract

In this paper, the application of palladium nanoparticles supported on hyperbranched poly (ethylene glycol)-block-poly(citric acid)-functionalized Fe3O4 magnetic nanoparticles (Pd@PCA-b-PEG-Fe3O4) were evaluated as a new electrocatalyst in electrochemical sensing. The Pd@PCA-b-PEG-Fe3O4 was immobilized on the surface of a glassy carbon electrode (GCE) for the electrochemical reduction of hydrogen peroxide (H2O2). This electrode material was characterized by scanning electron microscopy (SEM), the transmission electron microscopy (TEM), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). The Pd@PCA-b-PEG-Fe3O4 showed good electrocatalytic activity toward the reduction of H2O2 in the neutral phosphate buffer solution (pH 7.0). Moreover, the potential utility of the sensor was demonstrated by applying it to the analytical determination of H2O2 concentration. The results showed that the electrocatalytic current increased linearly with the H2O2 concentration in the range of 0.1–50.0 µM and the detection limit was 0.03 µM. Finally, the sensor has been successfully applied to determine H2O2 in water and urine samples with good accuracy and precision.