Flexible Carbon Electrodes for Electrochemical Detection of Bisphenol-A, Hydroquinone and Catechol in Water Samples

Acelino C De Sá,Simone C Barbosa,Paulo A Raymundo-Pereira,Maria Raposo,Flávio M Shimizu,Deivy Wilson,Osvaldo N Oliveira

doi:10.3390/chemosensors8040103

Abstract

The detection of pollutant traces in the public water supply and aquifers is essential for the safety of the population. In this article, we demonstrate that a simple electrochemical procedure in acidic solution can be employed for enhancing the sensitivity of flexible screen-printed carbon electrodes (SPEs) to detect bisphenol-A (BPA), hydroquinone, and catechol, simultaneously. The SPEs were pretreated electrochemically in a H2SO4 solution, which did not affect their morphology, yielding high current signals with well separated oxidation peaks. The sensitivity values were 0.28, 0.230, and 0.056 µA L µmol−1 with detection limits of 0.12, 0.82, and 0.95 µmol L−1 for hydroquinone, catechol, and BPA, respectively. The sensors were reproducible and selective for detecting BPA in plastic cups, and with adequate specificity not to be affected by interferents from water samples. The simple, inexpensive, and flexible SPE may thus be used to detect emerging pollutants and monitor the water quality.

Highlights

The detection of pollutant traces is crucial for guaranteeing the safety of public water supply and aquifers, which can be contaminated by pesticides [1], industrial products, personal hygiene pharmaceutical products (PPCPs) [2,3,4,5], and other emerging contaminants [6]
We demonstrate that a simple electrochemical procedure in acidic solution can be used to enhance the sensitivity of flexible screen-printed electrodes (SPEs) made with carbon-based materials which may be applied even to non-planar surfaces
As depicted in Scheme 1, the electrodes were made by printing a layer of carbon conductive ink BQ221 on the flexible polyethylene terephthalate (PET) substrate and dried in an oven at 90 ◦ C for 15 min

Summary

Introduction

The detection of pollutant traces is crucial for guaranteeing the safety of public water supply and aquifers, which can be contaminated by pesticides [1], industrial products, personal hygiene pharmaceutical products (PPCPs) [2,3,4,5], and other emerging contaminants [6] Among the latter contaminants, attention has been paid to plastic packaging containing bisphenol A (2,2-bis (4-hydroxyphenyl) propane) (BPA), a poorly water-soluble compound (5.2 × 10−4 mol L–1 ) used in manufacturing [7] of polycarbonate plastics and epoxy resins [4,8,9]. The concern about possible serious effects from BPA on the environment and humans has motivated the use of various detection methods, including enzyme-linked immune sorbent

Methods

Results

Conclusion