Sensitive Simultaneous Determination of o-Nitrophenol and p-Nitrophenol in Water by Surfactant-Mediated Differential Pulse Voltammetry

Author(s)

Capelari, Tainara Boareto ^[1] ; Pereira, Arnaldo Cesar ^[2] ; Goncalves de Oliveira, Leandro Luan ^[1] ; Teixeira Tarley, Cesar Ricardo ^{[1, 3]}

Affiliation

^[1] Univ Estadual Londrina, Ctr Ciencias Exatas, Dept Quim, Rodovia Celso Garcia Cid, Londrina, PR - Brazil

^[2] Univ Fed Sao Joao del Rei UFSJ, Dept Ciencias Nat, Sao Joao Del Rei, MG - Brazil

^[3] Univ Estadual Campinas UNICAMP, INCT Bioanalit, Inst Quim, Dept Quim Analit, Cidade Univ Zeferino Vaz S-N, Campinas, SP - Brazil

• Document type: Journal article
• Source: Analytical Letters; v. 52, n. 9, p. 1462-1476, JUN 13 2019.
• Web of Science Citations: 1

Abstract

A simple, low-cost and sensitive electroanalytical method was developed for the simultaneous determination of p-nitrophenol and o-nitrophenol isomers in water samples at a glassy carbon electrode (CGE) in the presence of cationic surfactant. The electrochemical behavior of p-nitrophenol and o-nitrophenol was studied by cyclic voltammetry (CV) in 0.1 mol L-1 acetate/acetic acid buffer (pH 3.70) in the presence and absence of cetylpyridinium bromide. The resolution of overlapped cathodic peaks potentials (E-pc) of isomers was successfully improved in the presence of 100.0 mu mol L-1 cetylpyridinium bromide, thus making this approach ideal for the simultaneous determination of isomers. Under the optimized conditions in 0.05 mol L-1 HEPES buffer at pH 7.0 using differential pulse voltammetry (DPV) at a scan rate of 45 mV s(-1), pulse amplitude of 220 mV and modulation time of 10 ms, limits of detection 0.59 mu mol L-1 for p-nitrophenol and 1.14 mu mol L-1 for o-nitrophenol were obtained with linear ranges from 2.0 to 60.0 mu mol L-1 and 3.0 to 60.0 mu mol L-1, respectively. The intraday precision was assessed as relative standard deviation (%) for 20.0 and 40.0 mu mol L-1 concentrations were 4.30% and 2.41% for p-nitrophenol and 4.87% and 2.20% for o-nitrophenol, respectively. The developed method was applied for the determination of the isomers in lake water samples. The accuracy was attested by comparison with high-performance liquid chromatography with diode array detection (HPLC-DAD) as a reference analytical technique. Recovery values ranging from 90.3% to 111.8% also attested to the accuracy of method for analysis of real samples. (AU)

• FAPESP's process: 14/50867-3 - INCT 2014: National Institute of Science and Technology in Bioanalysis
• Grantee: Marco Aurelio Zezzi Arruda
• Support Opportunities: Research Projects - Thematic Grants