Benzoate ion-selective electrode with improved selectivity and reproducibility for benzoate determination in medicinal syrups

• Tipo: Artigo em Revista Científica Internacional
• Data: 1996

Autores

Lima, JLFC (Autor) FFUP; Montenegro, MCBSM (Autor) FFUP; Sales, MGF (Autor) Outra

Revista

Título: Mikrochimica Acta

Vol. 124

Páginas: 35-41

ISSN: 0026-3672

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 12 Citações

Scopus - 10 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: P-001-FF6

DOI: 10.1007/bf01244954

Abstract (EN): This paper describes the construction and evaluation of a benzoate anion selective electrode with enhanced working characteristics, namely reproducibility and selectivity, to be used in medicinal syrups analysis by direct potentiometry. The electrode, without an internal reference solution, was prepared with a PVC membrane, based on bis(triphenylphosphoranylidene) ammonium benzoate as ion-exchanger, dissolved in 2-nitrophenyl octyl ether as mediator solvent and 4-t-octylphenol as additive. The characteristics of the electrodes were evaluated in sodium benzoate solutions with adjusted ionic strength and showed a linear response in the range 10(-2)-2 x 10(-4) mol dm(-3) with a slope of 54.7 +/- 0.5 mV/decade and a reproducibility of +/- 0.2 mV/day for solutions with pH 6.3. The potentiometric selectivity coefficients were determined for some possible interfering species and showed that the electrodes prepared with the additive had good selectivity, especially over iodide and nitrate, when compared with those without any additive. The electrodes were used for benzoate determinations in several medicinal syrups by direct potentiometry. The results gave recovery values in the range 98.3-104.6%.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7