Novel Electrochemical Sensor for Sunset Yellow Based on a Platinum Wire–Coated Electrode

Abstract

In this research, the construction and general performance characteristics of a sunset yellow sensor based on sunset yellow–cetyl pyridinum (SY-CPY) ion pair as an ion exchanger were described. A coated platinum wire electrode (CPE) was prepared and compared with coated graphite (CGE) and membrane electrode (PME). The CPE exhibited a rapid and Nernstian response (−29.77 ± 0.2 mV decade⁻¹) to SY concentration range from 3.16 × 10⁻⁷ to 3.16 × 10⁻³ mol dm⁻³ within pH 4.5–9.5. Interfering effects of some foreign substances were reported. The optimized matrix was successfully applied to the determination of SY in artificial mixtures and commercial soft drinks. The results showed good agreements with the determination made by use of high-performance liquid chromatography.

Keywords:

• Potentiometer
• sensor
• sunset yellow
• synthetic food colorant

The author thanks the Institute for Colorants, Paint, and Coatings (ICPC) for supporting this work.

Notes

∗Variation of potentiometric responses were measured at the concentration range of 1.0 × 10⁻¹ to 5.0 × 10⁻⁶ mol of SY solutions in phosphate buffers (pH 7.0), 25°C.

^a Mean ± standard deviation (n = 3).