Evaluation of a Nanocomposite Based on Reduced Graphene Oxide and Gold Nanoparticles as an Electrochemical Platform for Detection of Sulfamethazine

Martin Silva,Ivana Cesarino

doi:10.3390/jcs3020059

Martin Silva, Ivana Cesarino

Open Access

https://doi.org/10.3390/jcs3020059

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Abstract

A nanocomposite based on reduced graphene oxide (rGO) and gold nanoparticles (AuNPs) was synthesized by the microwave-assisted hydrothermal method and applied in the determination of sulfamethazine (SMZ) in swine effluent using a glassy carbon (GC) electrode. The rGO-AuNPs nanocomposite was characterized morphologically, electrochemically and spectrochemically, showing that rGO was modified with the AuNPs. The GC/rGO-AuNPs electrode was optimized for the determination of SMZ, achieving detection limits of 0.1 μmol L−1. The proposed sensor was successfully applied to the determination of SMZ in synthetic swine effluent samples.

Highlights

Sulfamethazine (SMZ), 4-amino-N-(4,6-dymethyl-2-pyrimide) benzenesulfonamide, is a frequently used sulfonamide with antibacterial properties to treat livestock disease such as gastrointestinal and respiratory tract infections in veterinary medicine [1]
The relative increase in the current values reflects the increase of the electroactive surface area, that is, a higher interaction of the analyte occurs with the active sites of the composite reduced graphene oxide (rGO)-AuNPs synthesized compared to the others, possibly caused by the insertion of the gold in the reduced graphene sheets
There were no significant differences between the found and added concentrations of SMZ, indicating that the glassy carbon (GC)/rGO-AuNPs could be successfully used for the determination of SMZ in swine effluent under the optimized conditions and using the standard addition approach

Summary

Introduction

Sulfamethazine (SMZ), 4-amino-N-(4,6-dymethyl-2-pyrimide) benzenesulfonamide, is a frequently used sulfonamide with antibacterial properties to treat livestock disease such as gastrointestinal and respiratory tract infections in veterinary medicine [1] This antibiotic is commonly used to promote growth [2] in swine production and its concentration in foodstuffs of animal origin is controlled by the European Commission (EC) which indicates a maximum level of 100 μg kg−1 for sulfonamide residue level [3,4,5,6]. Determining SMZ levels in natural samples, as swine farming effluent, is an important issue due to major ecotoxicological problems such as groundwater and drinking water contamination [7,8] In this way, the development of new analytical tools for determining low levels of SMZ is an extremely important. The proposed electrode is promising, allowing for the fast, simple, low cost, and sensitive determination of SMZ in environmental samples

Electroanalytical Procedures

Preparation of the Electrodes

Preparation of Swine Effluent Samples for SMZ Analysis

Characterization of the rGO-AuNPs Composite

Determination of SMZ in Synthetic Swine Effluent

Conclusions