Abstract

Introduction: The recognition of the health hazards of azo dyes has highlighted the need to develop efficient, rapid, and reliable analytical methods for dye determination.

Method: In this work, electrochemical probing of the azo group of Tartrazine (TZ) and Carmoisine (CR) in food dyes was carried out. Synthesized bismuth and zinc oxide nanoparticles were used to modify Graphite Electrode (GE).

Results: Electrochemical analysis showed a much better electrochemical response using ZnO+Bi/GE as a modifier than individually nanoparticle-modified graphite electrodes. From the CV analysis, it was found that both the dyes exhibited irreversible electrochemical behavior, and the redox parameters were calculated. The Limit of Detection (LOD) values recorded for TZ and CR for ZnO+Bi/GEbased sensors were 0.84 μM and 2.80 μM, respectively. The obtained sensitivity values were 11.86 μA/μM/cm² for TZ and 17.3 μA/μM/cm² for CR.

Conclusion: The sensor evidently demonstrated reliable simultaneous detection of both dyes, making it suitable for practical applications in food safety analysis.

Keywords: Azo dyes, sensor, electrochemical, bismuth, zinc oxide, voltammetry.