Disposable and low-cost electrochemical sensor based on the colorless nail polish and graphite composite material for tartrazine detection.

Affiliation

de Lima LF(1), Ferreira AL(2), Maciel CC(3), Ferreira M(2), de Araujo WR(4).
Author information:
(1)Portable Chemical Sensors Lab, Department of Analytical Chemistry, Institute of Chemistry, State University of Campinas - UNICAMP, P.O. Box 6154, 13083-970, Campinas, SP, Brazil.
(2)Center of Science and Technology for Sustainability
(CCTS), Federal University of São Carlos
(UFSCar), Sorocaba, SP, Brazil.
(3)Institute of Science and Technology, São Paulo State University
(UNESP), 18087-180, Sorocaba, Brazil.
(4)Portable Chemical Sensors Lab, Department of Analytical Chemistry, Institute of Chemistry, State University of Campinas - UNICAMP, P.O. Box 6154, 13083-970, Campinas, SP, Brazil. Electronic address: [Email]

Abstract

A new method to manufacture electrochemical devices based on the graphite and colorless nail polish (N-grap) film was developed for tartrazine (Tz) detection. Scanning Electron Microscopy (SEM) demonstrates that the composite material presents a high porous carbon structure. Cyclic voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) were employed to electrochemically characterize the electrode material, which corroborates the porous structure of the N-graph due to the enhanced electroactive area (5.4-fold increase) and presented a heterogeneous electron transfer rate constant (k0) of 5.82 × 10-3 cm s-1 for potassium ferricyanide. The electrochemical determination of the Tz was carried out using square-wave voltammetry (SWV), under the optimized experimental conditions, which showed high sensitivity (0.793 A L mol-1) and a lower limit of detection (LOD) of 2.10 × 10-8 mol L-1 with a linear concentration ranging from 2.0 to 50.0 μmol L-1. The developed sensor was applied for the analysis of Tz in sports drink samples and the result obtained by N-grap device was statistically compared with a spectrophotometric method demonstrating good accordance and the accuracy of the proposed method. Based on these results, we believe that this new fabrication method to produce disposable and low-cost electrochemical devices can be an alternative method for in-field analysis of dye in commercial sport drink samples and other relevant applications.