Hydrothermal synthesis of CuFeO nanoparticles for highly sensitive electrochemical detection of sunset yellow.

The sunset yellow, as a synthetic food coloring azo dye, was detected in the present work using a new sensitive and selective sensor based on the modification of screen-printed electrode surface with Copper ferrite nanoparticles (CuFeO/SPE). Thus, a facile hydrothermal protocol was performed to prepare the CuFeO nanoparticles, followed by characterization applying valid techniques, including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and field-emission scanning electron microscopy (FE-SEM). Chronoamperometry, differential pulse voltammetry (DPV) and cyclic voltammetry (CV) were employed to determine the electrochemical behavior of as-fabricated sensor. According to the electrochemical findings, a greater anodic peak current was found for the sunset yellow oxidation on the CuFeO/SPE than that on the unmodified SPE. The electrocatalytic response for the sunset yellow oxidation on the CuFeO/SPE in phosphate buffer (0.1 M, pH = 7.0) was effective, with an excellent sensitivity (0.1919 μA μM). There was a linear relationship between the voltammetric current and different sunset yellow concentrations (0.03-100.0 μM). The calculated limit of detection (LOD = 3Sb/m) for the sunset yellow was 0.009 μM.