Desenvolvimento de uma metodologia eletroanalítica para a determinação de pesticida anti-incrustante diuron em ambiente marinho

• Ano de defesa: 2017
• Autor(a) principal: Morita, Isabela Miyahira [UNIFESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Paulo
• Palavras-chave em Português: Electroanalysis; Antifouling; Diuron; Carbon nanotubes; MWCNT; Eletroanálise; Anti-incrustante; Nanotubos de carbono
• Link de acesso: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=5534675; http://repositorio.unifesp.br/handle/11600/49944

Considering the history of environmental impacts caused by antifouling contamination, it is necessary to monitor these biocides, among them the pesticide Diuron. In this bias the electroanalysis brings advantages such as fast readings and possibility of portability and in situ application of its systems. Furthermore, its association with carbon nanotubes (CNT) for sensor modification makes it possible to increase the sensitivity and selectivity of the methods. This work aimed to develop an electroanalytical methodology for the determination of Diuron in seawater with the aid of the techniques of cyclic voltammetry (CV), square wave voltammetry (SWV) and differential pulse voltammetry (DPV) with a glassy carbon electrode (GCE) modified with layers of a dispersion of functionalized MWCNTs, applied by casting. The qualitative studies, carried out by CV, aimed the identification and study of the oxidation process of Diuron. For the quantitative analyzes, performed by SWV and DPV, the parameters of each technique were optimized and the best number of MWCNT layers for GCE modification was studied. The calibration curves were delimited by standard addition and the LOD and LOQ of each technique were determined. The methodology developed by DPV GCE-MWCNT electrode - most sensitive - achieved LOD = 1.96 x 10-7 mol L-1 and LOQ = 6.53 x 10-7 mol L-1, results comparable to other methodologies described in literature. The applicability of the method was ascertained by two seawater recovery tests (76% and 124% recovery).