Electrochemical Method for Ease Determination of Sodium Diclofenac Trace Levels in Water Using Graphene-Multi-Walled Carbon Nanotubes Paste Electrode.

Sorina Motoc,Corina Orha,Anamaria Baciu,Aniela Pop,Florica Manea

doi:10.3390/ijerph19010029

Abstract

Sodium diclofenac (DCF) presence reported in water use cycle at various concentrations including trace levels necessitates continuous development of advanced analytical method for its determination. In this work, ease electrochemical methods for DCF determination based on voltammetric and amperometric techniques were proposed using a simple combination of graphene with multi-walled carbon nanotubes as paste electrode. Integration of the graphene with multi-walled carbon nanotubes enlarged the electroactive surface area of the electrode and implicitly enhanced the electrochemical response for DCF determination. On the basis of the sorption autocatalytic effect manifested at low concentration of DCF, we found that the preconcentration step applied prior to differential-pulsed voltammetry (DPV) and multiple-pulsed amperometry (MPA) allowed for the enhancement of the electroanalytical performance of the DCF electrochemical detections, which were validated by testing in tap water. The lowest limit of detection (LOD) of 1.40 ng·L−1 was found using preconcentration prior to DPV under optimized operating conditions, which is better than that reached by other carbon-based electrodes reported in the literature.

Highlights

Accepted: 18 December 2021Continuous improvement of the environmental quality represents one of the main important objectives of the global research activity efforts
Taking into account the advantages and disadvantages of voltammetric and amperometric techniques, as well as the detection purpose with the respect of the water type and matrix, we found that GR-carbon nanotubes (CNT) shows a great utility for practical application in the development of the screening method for the determination of DCF in any type of water body
The comparative electrochemical signal of the diclofenac onto graphene within multi-walled carbon nanotube paste electrode (GR-CNT) and CNT electrodes was characterized by cyclic voltammetry, and better voltammetric response was achieved for GR-CNT electrode

Summary

Introduction

Continuous improvement of the environmental quality represents one of the main important objectives of the global research activity efforts. Effective real-time monitoring based on advanced measurement methods represent the key to understanding and tackling the issue of water quality assurance and, in particular, of water contamination with pharmaceuticals, an actual issue addressed in terms of water quality. Pharmaceuticals administrated to humans or animals are excreted via urine and feces, with 30 to 90% of oral doses generally excreted as active substances [1,2,3,4]. Several variables, including the source and timing of pollution; wastewater treatment plant technology; operation and removal efficiency; the toxicity, degradation, persistence, and mobility properties of the pharmaceuticals; agriculture and veterinary practices; and the sensitivity of the receiving environment and exposure history, are responsible for the concentrations and impacts of Published: 21 December 2021

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Results

Conclusion