Potentiometric Sensors for the Selective Determination of Benzodiazepine Drug Residues in Real Wastewater Effluents

Sherif A Abdel-Gawad,Hany H Arab

doi:10.3390/chemosensors10020074

Abstract

The application of ion-selective electrodes (ISEs) in the detection and determination of environmental pollutants has become a very important mission in the last few years. Two selective and sensitive membrane electrodes were fabricated in the laboratory and intended to evaluate the electrochemical response of bromazepam (BRZ) using phosphotungstic acid (PTA) and sodium tetraphenylborate (TPB) as ion pairing agents. The linearity range of the fabricated electrodes was between 1 × 10−6 M to 1 × 10−3 M. Nernstian slopes of 54 mV/decade and 57 mV/decade were obtained for the BRZ-PTA and BRZ-TPB membrane electrodes, respectively. The performance of the fabricated membranes was optimum in the pH range of 3–6. Optimum electrochemical response was attained through the careful adjustment of all assay settings. The cited method was successfully applied for the selective determination of BRZ in either its pure form or real wastewater samples obtained from a pharmaceutical industrial plant. The main core of novelty in the suggested method lies in the application of the membranes for the sensitive, selective, and economic determination of BRZ in real wastewater effluents without the tedious sample pretreatment procedures. This can make the suggested method considered an eco-friendly method, as it minimizes the use of organic solvents and chemicals used in the pretreatment process.

Highlights

At each solution-membrane interface, BRZ molecules are selectively bonded with specific sites in the membrane (PTA or TPB)
Regarding the effect of plasticizers on the membrane performance, three different plasticizers were tried (NPOE, dibutyl sebacate (DBS), and Dioctyl phthalate (DOP)), which were of variable polarity
The novelty of this work originates from the absence of any published work dealing with the electrochemical determination of BRZ in real wastewater effluents

Summary

Introduction

Bromazepam (BRZ) is a classical benzodiazepine that is medically applied for the effective handling of insomnia, control of panic attacks, or anxiety. It gives its action by acting as a positive modulator that binds to gamma amino buteric acid (GABA)A receptors, performing a conformational alteration and increasing the inhibitory effects of GABA [1]. Regarding the International Narcotics Control Board (INCB), BRZ is a widespread used drug worldwide [2] This widespread use and the increase in its production may lead to its being present commonly in the wastewater effluents coming from pharmaceutical factories, which constitute an enormous risk on either the ecosystem or human health [3,4]

Methods

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Discussion

Conclusion