Electrochemical sensor for the detection of sunset yellow in food using a polyaniline/carbon nanopowder nanocomposite modified electrode

Abstract

Food items frequently face the risk of adulteration, which can lead to serious health consequences. An example of food fraud is the addition of synthetic azo dye sunset yellow (SY), for colouring food (SY-FCF). This study reports the design of an electrochemical sensor for the direct detection of SY at a glassy carbon electrode modified with a polyaniline (PANI) and carbon nanopowder (CNP) nanocomposite (GCE–PANI/CNP). The individual components of the sensor and the nanocomposite were characterised using FT-IR, UV-visible spectroscopy, XRD, SEM, and TEM. The developed electrochemical sensor (GCE/PANI/CNP) demonstrated optimal detection for SY using cyclic voltammetry and electrochemical impedance spectroscopy at approximately 0.8 V, compared to individual modified electrodes. The detection limit (LOD) was calculated to be 1.81 nM, with a broad linear detection range spanning from 1 to 194 nM, using square wave voltammetry. From the results obtained, it is concluded that the designed sensor can be a great tool for detecting sunset yellow in food samples.