Sol-gel thin-film based mesoporous silica and carbon nanotubes for the determination of dopamine, uric acid and paracetamol in urine

Autor(es)

Canevari, Thiago C. ^[1] ; Raymundo-Pereira, Paulo A. ^[1] ; Landers, Richard ^[2] ; Benvenutti, Edilson V. ^[3] ; Machado, Sergio A. S. ^[1]

Afiliação do(s) autor(es)

^[1] State Univ Sao Paulo, Inst Chem, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Fed Rio Grande do Sul, Inst Chem, BR-90046900 Porto Alegre, RS - Brazil

^[3] Univ Estadual Campinas, Inst Phys Gleb Wataghin, Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Talanta; v. 116, p. 726-735, NOV 15 2013.
• Citações Web of Science: 45

Resumo

This work describes the preparation, characterization and application of a hybrid material composed of disordered mesoporous silica (SiO2) modified with multiwalled carbon nanotubes (MWCNTs), obtained by the sol-gel process using HF as the catalyst. This hybrid material was characterized by N-2 adsorption-desorption isotherms, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission microscopy (HR-TEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). This new hybrid material was used for the construction of a thin film on a glassy carbon electrode. The modified electrode using this material was designated SiO2/MWCNT/GCE. The electrocatalytic properties of the electrode toward dopamine, uric acid and paracetamol oxidation were studied by differential pulse voltammetry. Well-defined and separated oxidation peaks were observed in phosphate buffer solution at pH 7.0, in contrast with the ill-defined peaks observed with unmodified glassy carbon electrodes. The electrode had high sensitivity for the determination of dopamine, uric acid and paracetamol, with the limits of detection obtained using statistical methods, at 0.014, 0.068 and 0.098 mu mol L-1, respectively. The electrode presented some important advantages, including enhanced physical rigidity, surface renewability by polishing and high sensitivity, allowing the simultaneous determination of these three analytes in a human urine sample. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 11/23047-7 - Desenvolvimento de biosensor eletroquímico utilizando sílica mesoporosa contendo nanotubos de carbono obtida pelo processo sol-gel. determinação eletroquímica de pesticidas
• Beneficiário: Thiago da Cruz Canevari
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 12/17689-9 - Preparação e caracterização de superfícies bifuncionais nanoestruturadas de Au-Pt obtidas via template para aplicação em sensores e biossensores
• Beneficiário: Paulo Augusto Raymundo Pereira
• Linha de fomento: Bolsas no Brasil - Doutorado