Electrochemical sensor based on multiwalled carbon nanotube and gold nanoparticle modified electrode for the sensitive detection of bisphenol A

A novel electrochemical sensor for bisphenol A comprising a multiwalled carbon nanotube (MWCNT) and gold nanoparticle (AuNP) composite modified glassy carbon electrode has been developed. Differential pulse voltammetric and electrochemical impedance characterisation were carried out. Modified electrode architectures with different MWCNT loadings and different numbers of deposited AuNP layers were tested, as well as the influence of pH. Under the best experimental conditions, the sensor exhibited a linear response to BPA from 0.01 mu M to 0.7 mu M, with a limit of detection of 4 nM, one of the lowest achieved up until now. The reproducibility, repeatability and stability of the sensor were examined and are superior to those reported in the literature using similar architectures for BPA sensors. Perspectives for an impedimetric sensor at micromolar concentrations were also assessed. Finally, the selectivity with respect to common interferents was demonstrated and practical application of the developed modified electrode for the determination of BPA in waters was successfully carried out. (C) 2017 Elsevier B.V. All rights reserved.