Simple Flow Injection Analysis System Coupled to Multiple‐Pulse Amperometry and a Boron‐Doped Diamond Electrode for the Simultaneous Determination of Sunset Yellow and Aspartame

Abstract

AbstractThe first electroanalytical method for the simultaneous determination of the colorant sunset yellow (SY) and the sweetener aspartame (AS) in commercial food samples is proposed using flow injection analysis coupled to multiple‐pulse amperometry (FIA‐MPA) and an anodically pretreated boron‐doped diamond electrode (APT‐BDDE). Dual‐potential waveforms are applied as a function of time: Edet.1=1.30 V/150 s for the oxidation only of SY, and Edet.2=1.70 V/200 s for the oxidation of both analytes. Linear analytical curves were obtained in the concentration range of 0.15–25.0 μmol L−1 for SY and 0.25–25.0 μmol L−1 for AS, with a calculated limit of detection of 0.04 μmol L−1 for both analytes. The proposed method presented good precision and enabled the simultaneous determination of SY and AS in samples of jelly and juice powders with a good accuracy (at a 95 % confidential level) when compared to an HPLC method. The proposed FIA‐MPA method is simple and fast, with an analytical frequency of 120 determinations per hour, being an attractive option for routine simultaneous determinations of SY and AS.