Development of a Novel Electrochemical Sensor Based on a Carbon Paste Electrode Decorated with Nd₂O₃ for the Simultaneous Detection of Tartrazine and Sunset Yellow

The simultaneous detection of tartrazine (TZ) and sunset yellow (SY) using a carbon paste-decorated neodymium (III) oxide electrode (Nd_Ox/CPE) is reported for the first time in this work. The surface properties of the Nd_Ox/CPE were studied by cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. The anodic peak currents for TZ and SY increased by more than 60 %, and the anodic peak potentials for TZ and SY were observed at potential values less positive than those of the carbon paste without Nd_OX. Under the optimal parameters (pH 3.0; accumulation time t_ACC 30 s; and accumulation potential E_ACC 0.10 V), the detection limits for TZ and SY observation were 0.02 μmol L⁻¹ (10.6 μg L⁻¹) and 0.09 μmol L⁻¹ (40.6 μg L⁻¹), respectively. The new sensor was sensitive, stable, easily manufactured, and very convenient for the detection of TZ and SY in food samples and pharmaceutical materials and provided consistent results.