Adsorptive detection of ethoxyquin on multi-walled carbon nanotube modified glassy carbon electrode

Abstract

Environmental and Analytical Chemistry Division, School of Advanced Sciences, Vellore Institute of Technology University, Vellore-632 014, Tamilnadu, India E-mail : [email protected] Ethoxyquin (EQ) is a common preservative used in several animal feeds such as fish, poultry and dairy food products. Excess addition of the EQ, (>75 ppm) to food products led to several health problems. Different analytical methods have been proposed for the determination of EQ in food samples. Unfortunately, existing methods are complicated and expensive. Here in, we report a selective and non enzymatic electro-analytical assay based on a multi-walled carbon nanotube modified glassy carbon electrode (GCE/MWCNT) with pH 7 of 0.1 M phosphate buffer solution for EQ analysis. A dilute ethanolic solution of EQ adsorbed GCE/MWCNT, i.e. GCE/MWCNT@EQ showed well-defined surface confined redox peak at –0.2 V vs Ag/AgCl, which is due to formation of a quinoline derivative on the interface. The peak potential and current values were taken as specific tool for the EQ quantification assays. Repeated experiment on unmodified GCE failed to show any such defined redox peak. The developed chemically modified electrode (CME) was characterized by Raman spectroscopy and FT-IR.