| Texto completo | |
| Autor(es): |
Wong, Ademar
[1]
;
Foguel, Marcos Vinicius
[1]
;
Khan, Sabir
[1]
;
de Oliveira, Fernanda Midori
[2]
;
Teixeira Tarley, Cesar Ricardo
[2]
;
Sotomayor, Maria D. P. T.
[1]
Número total de Autores: 6
|
| Afiliação do(s) autor(es): | [1] State Univ Sao Paulo UNESP, Dept Analyt Chem, Inst Chem, BR-14801970 Araraquara, SP - Brazil
[2] Univ Estadual Londrina, Dept Chem, BR-86050482 Londrina, PR - Brazil
Número total de Afiliações: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Electrochimica Acta; v. 182, p. 122-130, NOV 10 2015. |
| Citações Web of Science: | 24 |
| Resumo | |
An electrochemical sensor modified with a molecularly imprinted polymer (MIP) and carboxyl-functionalized multi-walled carbon nanotubes (MWCNT-COOH) was developed for the sensitive and selective detection of diuron in river water samples. An MIP was obtained by bulk polymerization using the best monomer (methacrylic acid) selected by computational simulation. The surface characteristics of the MIP and NIP (control polymer) samples were evaluated by means of surface area and pore volume determinations, using the BET method. The adsorption efficiency of the MIP was determined in adsorption tests that revealed high adsorption, relative to the control polymer. In addition, MWCNTs functionalized with carboxyl groups were used to enhance the performance of the sensor. Electrochemical studies of diuron using the MIP and MWCNT-COOH immobilized on a carbon paste electrode were performed with wave square voltammetry (SWV). The analytical parameters pH, buffer composition, and amounts of MWCNT-COOH and MIP were investigated and optimized. Excellent results were obtained with a linear range of between 5.2 x 10(-8) and 1.25 x 10(-6) mol L-1, detection limit of 9.0 x 10(-9) mol L-1, and sensitivity of 5.1 x 10(5) mu A L mol(-1). The MWCNT-COOH-MIP/CPE showed an enhanced electrochemical response, with sensitivity 7.9-fold greater than for a plain carbon paste electrode (CPE). Application of the sensor using river water samples resulted in recoveries between 96.1 and 99.5% and RSD <5% (n=3), demonstrating the reliability of this device. (C) 2015 Elsevier Ltd. All rights reserved. (AU) | |
| Processo FAPESP: | 11/03008-7 - Desenvolvimento de sensores eletroquímicos e métodos de extração em fase sólida baseados em sistemas biomiméticos para análise de poluentes ambientais |
| Beneficiário: | Ademar Wong |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 14/25264-3 - Desenvolvimento e aplicação de novos sensores químicos nanoestruturados baseados em polímeros biomiméticos |
| Beneficiário: | Maria Del Pilar Taboada Sotomayor |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |