A Carbon Black-Based Non-Enzymatic Electrochemical Sensor for the Detection of Sunset Yellow in Beverages

This study presents a highly sensitive non-enzymatic electrochemical sensor for detecting Sunset Yellow, a common food additive in beverages, based on palladium-cerium oxide composite decorated carbon black (CB). The sensing material was prepared by depositing palladium nanoparticles onto cerium oxide nanocubes, followed by the uniform dispersion of CB through sonication in a water bath. The strong metal–support interaction between palladium and cerium oxide significantly enhances catalytic activity, while the CB ensures excellent conductivity and structural support for the catalyst. Under optimized conditions, the sensor exhibits a linear response to Sunset Yellow concentrations in the range from 1 to 100 nM, with a limit of detection (LOD) of 0.056 nM. Additionally, the sensor demonstrates remarkable selectivity and stability. Practical application in real orange juice samples yielded recoveries from 99.11% and 101.34%, confirming its reliability for real-world beverage analysis.