Ultrasensitive determination of ceftizoxime using pencil graphite electrode modified by hollow gold nanoparticles/reduced graphene oxide

Abstract In this work, a pencil graphite electrode (PGE) was modified using electrochemically reduced graphene oxide (rGO) and then hollow gold nanoparticles (HGNPs) were generated onto rGO/PGE by electrodeposition of cobalt and after that galvanic displacement reaction of cobalt nanoparticles with Au 3+ ions. In this way, hollow gold nanoparticles/reduced graphene oxide/pencil graphite electrode (HGNPs/rGO/PGE) was constructed and used for sensitive voltammetric determination of ceftizoxime (CFX). The design experiment as a central composite design (CCD) methodology was developed as the experimental strategy for optimization of the influence of variables on the performance of modified electrode. The modified electrode was characterized using electrochemical impedance spectroscopy (EIS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and choronocoulometry. The cyclic voltammetry (CV) and adsorptive differential pulse voltammetry (AdDPV) methods were utilized to survey the electrochemical action of CFX on the modified electrode. The linear dynamic range was 1.0 × 10 - 12 M to 1.0 × 10 - 11 M and 1.0 × 10 - 11 M to 1.0 × 10 - 9 M with a detection limit of 3.5 × 10 −13 M. The existent method was employed to the determination of CFX in pharmaceutical and biological samples.