Voltammetric nanostructure based sensor for determination of Sudan I in food samples

Abstract

Ionic liquid/CdO/NPs carbon paste electrode (IL/CdO/NPs/CPE) has been used as a high sensitive sensor for the professional quantitative determination of sudan I in food samples in aqueous solution. In the first step, CdO/NPs synthesis using chemical precipitation method and characterized with different methods such as transmission electron microscopy (TEM) and X-ray diffraction (XRD). The propose sensor shows a better electrochemical response with lower over-potential and high sensitivity for sudan I compared with unmodified carbon paste electrode using linear sweep voltammetry (LSV). The electro-oxidation of sudan I occurred in a pH-dependent e- and H+ process, and the electrode reaction followed a diffusion-controlled pathway. Under the optimum conditions in square wave voltammetry (SWV), the voltammetric oxidation peak current of sudan I showed linear dynamic ranges with a detection limit of 0.05 µM for sudan I. The modified electrode was successfully used for the determination of the analytes in real samples with satisfactory result. © 2015 The Authors.