Electrochemical detection of indigo carmine in candies using Y2O3 nanoparticles infused graphite electrode

This article presents the use of Yttrium Oxide (Y2O3) nanoparticles to modify the graphite paste electrode (GPE) for the sensitive and selective electrochemical determination of Indigo Carmine (ICN), one of the well-known synthetic food colorants. These nanoparticles were formed via a simple sol and gel method and characterized by a few non-destructive analytical methods like X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDX) techniques. The electrode response was studied via Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV) methods for the variation of some fundamental parameters such as buffer, pH, scan rates, and concentrations. The efficiency of the developed Yttrium Oxide (Y2O3) nanoparticles modified Graphite Paste Electrode (Y2O3@GPE) sensor was assessed via repeatability, reproducibility and long-term stability analysis. Various similar interferants were added with ICN molecules for accomplishing the selectivity study while a widely linear operating range with a Limit of Detection (LOD) and a Limit of Quantitation (LOQ) of 0.11 µM and 0.35 µM, respectively were found. The performance of the electrode was justified in the real samples through its application for the detection of ICN in different candies where a satisfactory recovery rate of 96.25 %-117.5 % was achieved.