Simultaneous determination of environmental contaminants using a graphite oxide – Polyurethane composite electrode modified with cyclodextrin

• Published in: Materials Science & Engineering C 2019-06, Vol.99, p.1415-1423
• Main Authors: Wong, Ademar, Santos, Anderson Martin, Baccarin, Marina, Cavalheiro, Éder Tadeu Gomes, Fatibello-Filho, Orlando
• Format: Article
• Language: English
• Subjects: Confidence intervals; Contaminants; Cyclodextrins; Electrodes; Energy dispersive X ray spectroscopy; Environmental contaminants; Graphite; Graphite oxide; Graphite oxide-polyurethane composite electrode; Materials science; Nimesulide; Polyurethane; Polyurethane resins; Potassium chloride; Rivers; Scanning electron microscopy; Sensor arrays; Silver chloride; Simultaneous determination; Spectrophotometry; Terbutaline; Thermogravimetry; Voltammetry; Water analysis; Water pollution; Water sampling; X-ray spectroscopy; β-Cyclodextrin
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2019.02.093

A composite electrode based on graphite oxide (GrO)-polyurethane (PU) modified with β-cyclodextrin (CD) was proposed for the simultaneous determination of three drugs: terbutaline (TER), nimesulide (NIM), and methocarbamol (MET), as possible contaminants in river water samples. To evaluate the performance of the proposed CD-GrOPUE, voltammetric techniques were used and two other electrodes were fabricated (GrOPUE and GrPUE) for comparison. The functionalization of the GrO was confirmed by scanning electron microscopy images, energy-dispersive X-ray spectroscopy analysis, and thermogravimetry. Cyclic voltammograms obtained for TER, NIM, and MET indicated an irreversible behaviour at 0.6 V, 0.9 V and 1.2 V (vs. Ag/AgCl (3 mol L−1 KCl)), respectively, on each working electrode, with the highest peak current values been obtained using the CD-GrOPUE. Under optimal conditions, using square-wave voltammetry, the linear ranges obtained (and limit of detection) for TER, NIM, and MET were 2.5–30 (0.55), 0.62–7.3 (0.083), and 0.62–7.3 (0.077) μmol L−1, respectively. The analytical method developed were applied in the simultaneous determination of TER, NIM, and MET in river water samples, with results like those obtained using a reference spectrophotometric method (at a confidence level of 95%). One can conclude, that the modification of GrO with CD arrays made possible the development of a robust and simple sensor platform for environmental analyses. [Display omitted] •GrOPU electrode modified with β-cyclodextrin•Simultaneous detection of terbutaline, nimesulide and methocarbamol•Increase of anodic peak current (catalytic profile)•Sensor showed good stability and repeatability.•Determination of environmental contaminants in river water samples