Simultaneous determination of ascorbic acid, acetaminophen and codeine based on multi-walled carbon nanotubes modified with magnetic nanoparticles paste electrode.

Based on incorporating ZnCrFeO4 into multi-walled carbon nanotubes paste matrix (MWCNTs/ZnCrFeO4/CPE), a chemically modified electrode was prepared for the simultaneous determination of ascorbic acid (AA), acetaminophen (AC) and codeine (CO). The prepared electrode, MWCNTs/ZnCrFeO4/CPE, was characterized by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The MWCNTs/ZnCrFeO4/CPE showed an efficient electrocatalytic activity for the oxidation of AA, AC, and CO. The separations of the oxidation peak potentials for AA-AC and AC-CO were about 250mV and 630mV, respectively. The calibration curves obtained for AA, AC, and CO were in the ranges of 0.4-730.0μmolL(-1), 0.1-368.0μmolL(-1), and 0.3-250.0μmolL(-1), respectively. The detection limits (S/N=3) were 0.03μmolL(-1), 0.009μmolL(-1), and 0.01μmolL(-1) for AA, AC, and CO, respectively. The method was also successfully employed as a selective, simple, and precise method to determinate AA, AC, and CO in pharmaceutical and biological samples.