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Orientador(es)
Resumo(s)
A picrate ion-selective electrode without inner reference solution and based on bis(triphenylphosphoranylidene)ammonium picrate dissolved in 2-nitrophenyloctyl ether was constructed and its characteristics assessed. With respect to reducing sugar determination in Port wine, a tubular electrode based on the same sensor system was developed and incorporated into a flow-injection manifold devised for this determination. The methodology involves a reaction between the reducing sugar and picric acid, the decrease in the picrate concentration being monitored with the tubular electrode. A linear dependence between peak width, at a fixed potential and the logarithm of sugar concentration in the range 25–200 g l−1 was obtained. The proposed system allows wine samples to be injected with no previous treatment and allows a sample throughput of 50 determinations per hour, a relative standard deviation less than 4%, and the results are comparable to the reference procedures.
Descrição
Palavras-chave
Flow injection Ion selective electrodes Picrate Sugar Wine
Contexto Educativo
Citação
LOPES, Teresa I. M. S....[et al] - Construction and use of a tubular picrate ion-selective electrode for reducing sugar determination in Port wine by flow-injection analysis. Analytica Chimica Acta. ISSN 0003.2670. Vol. 308 n.º 1-3 (1995), p.122-128
Editora
Elsevier