Simultaneous Voltammetric Determination of Zn(II), Pb(II), Cu(II), and Hg(II) in Ethanol Fuel Using an Organofunctionalized Modified Graphite-Polyurethane Composite Disposable Screen-Printed Device

Author(s)

Saciloto, Thalita R. ^[1] ; Cervini, Priscila ^[1] ; Cavalheiro, Eder T. G. ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Chem Sao Carlos, BR-13566590 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Electroanalysis; v. 26, n. 12, p. 2664-2676, DEC 2014.
• Web of Science Citations: 12

Abstract

A disposable screen-printed device containing working, auxiliary, and reference electrodes is proposed for the simultaneous voltammetric determination of Zn(II), Pb(II), Cu(II), and Hg(II) in ethanol fuel. The working electrode was printed using an ink modified with 2-benzothiazole-2-thiol organofunctionalized SBA-15 silica, in order to increase sensitivity. The performance of this electrode was compared with that of bare and SBA-15-modified electrodes. After optimizing the experimental parameters, the device was applied in determination of the analytes in commercial ethanol fuel samples, using 0.10 mol L-1 KCl/ethanol ratios of 30 : 70 (v/v), with {[}H+]=10(-5) mol L-1. After 5 min of preconcentration at -1.3 V (vs. pseudo-Ag/AgCl), four well-resolved signals were obtained, enabling simultaneous determination of the four analytes using a differential pulse anodic stripping voltammetry (DPASV) procedure. The limits of detection were 0.30, 0.065, 0.030, and 0.046 mu mol L-1 for Zn(II), Pb(II), Cu(II), and Hg(II), respectively. The results of these analyses were in agreement with those obtained using graphite furnace atomic absorption spectroscopy (GFAAS) for Pb(II), Cu(II), and Hg(II), and high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) for Zn2+, at a 95% confidence level. Analytes originally present in the samples could be detected, and the interference of some cations and anions was evaluated. (AU)

• FAPESP's process: 10/11080-7 - Preparation and application of grafite-polimer based composite electrodes : modification with organofunctionalized silicas and molecurlay imprinted polymers
• Grantee: Éder Tadeu Gomes Cavalheiro
• Support Opportunities: Regular Research Grants
• FAPESP's process: 10/05913-6 - Development and application of screen printed electrodes based on graphite and polyurethane composites
• Grantee: Thalita Rocha Saciloto
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)