Ionic medium effects on equilibrium constants Part I. Proton, copper(II), cadmium(II), lead(II) and acetate activity coefficients in aqueous solution

Pezza, Leonardo; Molina, M.; Moraes, Mercedes de; Melios, C. B.; Tognolli, João Olímpio

doi:10.1016/0039-9140(96)01944-3

Cited by 23 publications

(29 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…46,47 Metallic mercury was purified according to a previously reported procedure. 46 Hg 2 (Fur) 2 was prepared by mixing, in aqueous solution, the corresponding nitrate with an excess of NaFur. The resulting precipitate was filtered through a sintered glass funnel, washed with deionized water until nitrate free, and then dried in a desiccator, over calcium chloride under reduced pressure, at room temperature, to constant mass.…”

Section: Reagentsmentioning

confidence: 99%

See 1 more Smart Citation

Potentiometric sensor for furosemide determination in pharmaceuticals, urine, blood serum and bovine milk

Santini¹,

Pezza²,

Sequinel³

et al. 2009

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

A construção, avaliação e aplicação analítica de um sensor potenciométrico do tipo PtHgHg 2 (Fur) 2 Grafite, onde Fur significa íon 4-cloro-N-furfuril-5-sulfamoil-antranilato, são descritas. O eletrodo responde a Fur com sensibilidade de (−58,4 ± 0,9) mV década -1 no intervalo de 5,0 × 10 -7 -1,0 × 10 -2 mol L -1 , a pH 7,0-9,0 e com um limite de detecção de 3,8 × 10 -7 mol L -1 . O eletrodo é facilmente construído e de baixo custo, apresenta um rápido tempo de resposta (10-20 s) e pode ser usado por um período de 6 meses sem qualquer variação considerável nas suas características de desempenho. O eletrodo proposto mostrou boa seletividade na presença de várias substâncias, bem como na presença de alguns carboxilatos e ânions inorgânicos. O eletrodo foi aplicado com sucesso na determinação de furosemida em medicamentos, urina, soro sanguíneo e amostras comerciais de leite bovino.The construction, evaluation and analytical application of a potentiometric sensor, namely, PtHgHg 2 (Fur) 2 Graphite, where Fur stands for 4-chloro-N-furfuryl-5-sulphamoyl-anthranilate ion, are described. This electrode has a linear dynamic range between 5.0 × 10 -7 -1.0 × 10 -2 mol L -1 with a near-Nernstian slope of (-58.4± 0.9) mV decade -1 and a detection limit of 3.8 × 10 -7 mol L -1 . The potentiometric response is independent of the pH of the solution in the pH range 7.0-9.0. The electrode shows easy construction, low-cost, fast response time (within 10-20 s) and can be used for a period of 6 months without significant change in its performance characteristics. The proposed sensor displayed good selectivities over a variety of other anions (carboxylates and inorganic anions). Application of this potentiometric sensor for the furosemide determination in pharmaceuticals, urine, blood serum and commercial milk samples is reported.Keywords: 4-cloro-N-furfuryl-5-sulphamoylanthranilate-sensitive electrode, potentiometry, pharmaceuticals, urine, human blood serum, bovine milk IntroductionFurosemide or frusemide (HFur, 4-chloro-N-furfuryl-5-sulphamoyl-anthranilic acid) is formally a sulfonamide, an antibacterial agent (Figure 1). However, the intense and fast dieresis produced by this drug has extended its application as a powerful acidic diuretic for diverse treatments in humans and veterinary medicine. Furosemide is often classified as a loop diuretic due to its predominant action in the nephron, where the drug interferes with the tubular re-absorption of sodium on Henle's loop. 1 The renal excretion of ions is not limited to sodium and chloride, but it may also influence potassium, magnesium, calcium and, to a lesser extent, hydrogen carbonate ions. 2 In the clinical practice, the effects of furosemide are applied in the treatment of edema associated with pulmonary, cardiac, hepatic and renal disease, and of hypertension accompanied by fluid retention or impaired renal failure. 3-7 A marked diuresis is also associated to loss of weight, a side effect that has been incorrectly abused in the sport practice to achieve acute weight ...

show abstract

Section: Reagentsmentioning

confidence: 99%

Section: Reagentsmentioning

confidence: 99%

Potentiometric sensor for furosemide determination in pharmaceuticals, urine, blood serum and bovine milk

Santini¹,

Pezza²,

Sequinel³

et al. 2009

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

show abstract

“…33 This sodium flufenamate stock solution was analyzed by evaporating and drying to constant weight at 120 o C. Standardizations of carbonate-free sodium hydroxide, nitric acid and sodium nitrate solutions were performed as described elsewhere. 26,31 Metallic mercury was purified according to a previously reported procedure. 34 Mercury (I) flufenamate was prepared by mixing, in aqueous solution, the corresponding nitrate with an excess of sodium flufenamate.…”

Section: Reagentsmentioning

confidence: 99%

“…Previous work from this laboratory dealt with the development of mercury(I)-carboxylate electrodes and their application to solution equilibria, [26][27][28][29] food analysis, 30 and pharmaceutical analysis 31,32 involving carboxylate bearing compounds.…”

Section: Introductionmentioning

confidence: 99%

“…1, 2008 To the best of our knowledge, there are a single report on the use of ion-selective potentiometric sensor for the determination of flufenamic acid. 25 However, this electrode has not been applied for the determination of FFA in pharmaceuticals and biological fluids, thus, precluding the assessment of its usefulness in real analysis.Previous work from this laboratory dealt with the development of mercury(I)-carboxylate electrodes and their application to solution equilibria, [26][27][28][29] food analysis, 30 and pharmaceutical analysis 31,32 involving carboxylate bearing compounds.The aim of the present contribution was to develop a simple and low-cost potentiometric flufenamate ISE immobilized in a graphite matrix (Pt Hg Hg 2 (FF) 2 Graphite, where FF stands for flufenamate ion) and to evaluate the applicability of this sensor to the determination of FFA in dosage forms and human serum samples. …”

mentioning

confidence: 99%

See 1 more Smart Citation

Development of a potentiometric flufenamate ISE and its application to pharmaceutical and clinical analyses

Santini¹,

Pezza²,

Oliveira³

et al. 2008

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

As características, o desempenho e a aplicação de um eletrodo do tipo Pt Hg Hg 2 (FF) 2 Grafite, FF=íon flufenamato, são descritas. O eletrodo responde a FF com sensibilidade de (-58,6 1,2) mV década -1 no intervalo de 1,0 10 -6 -1,0 10 -2 mol L -1 , a pH 6,0 -9,0 e com um limite de detecção de 7,1 10 -7 mol L -1 . O eletrodo é de custo relativamente baixo e facilmente construído, apresenta um rápido tempo de resposta (10-25 s) e pode ser usado por um período de 5 meses sem qualquer variação considerável nas suas características de desempenho. O eletrodo proposto mostrou boa seletividade para o íon flufenamato na presença de várias substâncias, bem como na presença de alguns carboxilatos e ânions inorgânicos. O eletrodo foi aplicado com sucesso na determinação de ácido flufenâmico em medicamentos e amostras de soro humano.The characteristics, performance, and application of an electrode, namely, Pt Hg Hg 2 (FF) 2 Graphite, where FF stands for flufenamate ion, are described. This electrode responds to FF with sensitivity of (-58.6 1.2) mV decade -1 over the range 1.0 10 -6 -1.0 10 -2 mol L -1 at pH 6.0 -9.0 and a detection limit of 7.1 10 -7 mol L -1. The electrode is easily constructed at a relatively low cost with fast response time (within 10-25 s) and can be used for a period of 5 months without any considerable change in its performance characteristics. The proposed electrode displayed good selectivity for flufenamate in the presence of several substances as well as in the presence of some carboxylate and inorganic anions. The electrode was successfully applied to the determination of flufenamic acid in pharmaceuticals and human serum samples.Keywords: flufenamate-sensitive electrode, potentiometry, dosage forms, blood serum IntroductionFlufenamic acid (FFA), [N-( , , -trifluoro-m-tolyl) anthranilic acid] is an analgesic, anti-inflammatory and antipyretic drug. It is extensively used in the treatment of arthritis and other illnesses related to muscular-skeletal problems.1 However the use of this drug has been implicated in some cases of nephrotoxicity.2 Due to the importance of the assay of FFA for pharmaceutical formulations and biological fluids, several analytical methods have been developed for the quantitative determination of this drug in both pharmaceutical and biological samples.These methods include spectrophotometry, 21,22 However, many of these methods are often time-consuming, technically demanding and require the use of costly, highly specialized instruments. Thus, there is an important demand for simple, low-cost, sensitive and rapid alternative methods for the determination of FFA in pharmaceuticals and biological fluids.Potentiometric methods with ion-selective electrodes (ISE's) have proved to be effective for the analysis of pharmaceutical formulations and biological samples, because these sensors offer the advantages of simple design, construction, and manipulation, reasonable selectivity, fast response time, applicability to colored and turbid solutions and possible interfacing with au...

show abstract

An Electrode of the Second Kind for Benzoate Determination in Medicinal Syrups

Peres

Moraes

Pezza

et al. 1998

Microchemical Journal

View full text Add to dashboard Cite

Ionic medium effects on equilibrium constants Part I. Proton, copper(II), cadmium(II), lead(II) and acetate activity coefficients in aqueous solution

Cited by 23 publications

References 14 publications

Potentiometric sensor for furosemide determination in pharmaceuticals, urine, blood serum and bovine milk

Potentiometric sensor for furosemide determination in pharmaceuticals, urine, blood serum and bovine milk

Development of a potentiometric flufenamate ISE and its application to pharmaceutical and clinical analyses

An Electrode of the Second Kind for Benzoate Determination in Medicinal Syrups

Contact Info

Product

Resources

About