Disposable Electrochemical Sensor for Food Colorants Detection by Reduced Graphene Oxide and Methionine Film Modified Screen Printed Carbon Electrode

Abstract

A facile synthesis of reduced graphene oxide (rGO) and methionine film modified screen printed carbon electrode (rGO-methionine/SPCE) was proposed as a disposable sensor for determination of food colorants including amaranth, tartrazine, sunset yellow, and carminic acid. The fabrication process can be achieved in only 2 steps including drop-casting of rGO and electropolymerization of poly(L-methionine) film on SPCE. Surface morphology of modified electrode was studied by scanning electron microscopy (SEM). This work showed a successfully developed novel disposable sensor for detection of all 4 dyes as food colorants. The electrochemical behavior of all 4 food colorants were investigated on modified electrodes. The rGO-methionine/SPCE significantly enhanced catalytic activity of all 4 dyes. The pH value and accumulation time were optimized to obtain optimal condition of each colorant. Differential pulse voltammetry (DPV) was used for determination, and two linear detection ranges were observed for each dye. Linear detection ranges were found from 1 to 10 and 10 to 100 µM for amaranth, 1 to 10 and 10 to 85 µM for tartrazine, 1 to 10 and 10 to 50 µM for sunset yellow, and 1 to 20 and 20 to 60 µM for carminic acid. The limit of detection (LOD) was calculated at 57, 41, 48, and 36 nM for amaranth, tartrazine, sunset yellow, and carminic acid, respectively. In addition, the modified sensor also demonstrated high tolerance to interference substances, good repeatability, and high performance for real sample analysis.

Electropolymerized 4-Aminobenzoic Acid Based Voltammetric Sensor for the Simultaneous Determination of Food Azo Dyes

“…Furthermore, the determination is based on the oxidation signal, which excludes the use of inert gas for the removal of oxygen affecting the reduction signals of the dyes, as was observed in [43,44]. Better analytical characteristics were obtained at the electrode modified with polypyrrole decorated oxidized single-walled carbon nanotubes [45]; however, the adsorptive preconcentration step takes 5 min,, rendering the method time-consuming. In addition, this step can lead to the co-preconcentration of other components of the sample.…”

“…Amino acids, particularly L-cysteine, are the most often used monomer. The oxidative electropolymerization in the potentiodynamic mode is used for the polymeric coverage formation [39][40][41][42][43][44][45][46]. Both reduction and oxidation currents can be successfully used as analytical signals.…”

An efficient CuO/rGO/TiO2photocatalyst for the synthesis of benzopyranopyrimidine compounds under visible light irradiation

“…64 The oxidation/reduction peaks recorded using GC-modified rGO and rGO/TiO 2 electrodes revealed an increase in anodic and cathodic currents compared to those recorded using a bare GCE, which can be assigned to the favourable role of rGO in accelerating the electron transfer 65 because of its high surface area. 66 The comparison of the oxidation/reduction peaks acquired on GC–CuO/rGO/TiO 2 showed obvious enhancement in the anodic and cathodic currents, which illustrates the role of rGO 66 and the synergistic effect between copper nanoparticles and rGO sheets in the CuO/rGO/TiO 2 nanocomposite. 67…”

Carbon Nanomaterials-Based Screen-Printed Electrodes for Sensing Applications

“…Because of this, control of the levels of dyes that are added to food is necessary. On this topic, Akkapinyo et al [ 54 ] constructed a rGO-methionine-modified SPCE for the investigation of the dyes amaranth, tartrazine, twilight yellow, and carminic acid. The poly(amino acid) increased the electrocatalytic activity of the sensor and increased the number of active sites for interaction with the target analytes.…”