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1.
Talanta ; 84(1): 34-41, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21315894

RESUMO

In this article a new coated platinum Cu(2+) ion selective electrode based on 2-((2-(2-(2-(2-hydroxy-5-methoxybenzylideneamino)phenyl)disufanyl)phenylimino) methyl)-4-methoxyphenol Schiff base (L(1)) as a new ionophore is described. This sensor has a wide linear range of concentration (1.2 × 10(-7)-1.0 × 10(-1) mol L(-1)) and a low detection limit of 9.8 × 10(-8) mol L(-1)of Cu(NO(3))(2). It has a Nernstian response with slope of 29.54 ± 1.62 mV decade(-1) and it is applicable in the pH range of 4.0-6.0 without any divergence in potential. The coated electrode has a short response time of approximately 9s and is stable at least for 3.5 months. The electrode shows a good selectivity for Cu(2+) ion toward a wide variety of metal ions. The proposed sensor was successfully applied for the determination of Cu(2+) ion in different real and environmental samples and as indicator electrode for potentiometric titration of Cu(2+) ion with EDTA.


Assuntos
Compostos de Benzil/química , Cobre/química , Bases de Schiff/química , Café/química , Cobre/análise , Eletrodos , Concentração de Íons de Hidrogênio , Limite de Detecção , Membranas Artificiais , Águas Minerais/análise , Platina/química , Cloreto de Polivinila/química , Potenciometria , Reprodutibilidade dos Testes , Rios/química , Solventes/química , Fatores de Tempo , Água/química
2.
J Hazard Mater ; 178(1-3): 157-63, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20362393

RESUMO

A new chromium carbon paste electrode sensor based on a carbon paste electrode containing 1-[(2-hydroxy ethyl) amino]-4-methyl-9H-thioxanthen-9-one (AMTX) as new carrier has been prepared. The influence of carbon paste ingredients including sodium tetraphenylborate (NaTPB), ionophore, Nujol and graphite powder on the electrode response has been investigated. The best performance characteristics for the electrode was obtained with a carbon:NaTPB:Nujol:AMTX in the mass ratio of (400:1.43:57.2:3mg) (86.65:0.31:12.39:0.65%). At the optimum value of all variables, the response of electrode is linear in range of 3.2x10(-7) to 1.0x10(-1)mol L(-1) with a Nernstian slope of 20.51 mV decade(-1) of Cr(3+) ion concentration with detection limit of 1.6x10(-7)mol L(-1). The electrode response is independent of pH in the range of 4.8-6.3, while the response time of the electrode was approximately 8 s. The potentiometric selectivity coefficients of proposed chromium-selective electrode towards various interfering ions were determined by fixed interference method (FIM), separate solution method (SSM) and matched potential method (MPM).


Assuntos
Cromo/química , Tioxantenos/química , Xantonas/química , Café/química , Dimetil Sulfóxido , Eletroquímica , Eletrodos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Resíduos Industriais/análise , Ligantes , Membranas Artificiais , Permeabilidade , Petróleo/análise , Potenciometria , Padrões de Referência , Solventes , Espectrofotometria Ultravioleta , Chá/química , Abastecimento de Água/análise
3.
J Hazard Mater ; 166(2-3): 1441-8, 2009 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-19200648

RESUMO

A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in food samples has been reported. The method is based on the adsorption of zinc, nickel, iron and lead on sodium dodecyl sulfate (SDS)-coated alumina, which is also chelated with bis (2-hydroxyacetophenone)-1, 3-propanediimine (BHAPN). The retained analyte ions on modified solid phase were eluted using 8 mL of 4 mol L(-1) HNO(3). The analyte determinations were carried out by flame atomic absorption spectrometry. The influences of some metal ions and anions on the recoveries of understudy analyte ions were investigated. The proposed method has been successfully applied for the evaluation of these trace and toxic metals in some traditional food samples from Iran.


Assuntos
Quelantes/química , Metais Pesados/análise , Extração em Fase Sólida/métodos , Óxido de Alumínio/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Ferro/análise , Chumbo/análise , Níquel/análise , Dodecilsulfato de Sódio/química , Espectrofotometria Atômica/métodos , Zinco/análise
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