Membrane sensors for the selective determination of fluorouracil

Hassan, Saad S. M.; Amer, M. M.; El-Fatah, Soheir A. Abd; El-Kosasy, Amira M.

doi:10.1016/s0003-2670(98)00062-2

Cited by 38 publications

(22 citation statements)

References 9 publications

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“…The response time of the ketoconazoleselective electrode was investigated. [20][21][22] Stable responses were achieved within 30 -60 s for concentrations of 10 -3 -10 -6 mol dm -3 . The electrode exhibited a day-to-day reproducibility of about ±1.5 mV for the same ketoconazole solutions for 4 weeks after preparation.…”

Section: Resultsmentioning

confidence: 90%

“…These make ISE potentiometry very attractive for pharmaceutical analysis. [20][21][22] In this paper, we describe a simple potentiometric PVC-membrane sensor for the determination of ketoconazole in pharmaceutical preparations and in biological matrices. The membrane used in this electrode was made from liquid-plasticized PVC and was based on a water-insoluble ketoconazole-tetraphenylborate ion pair as an ion-exchanger.…”

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confidence: 99%

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Preparation of a Ketoconazole Ion-Selective Electrode and Its Application to Pharmaceutical Analysis

Shamsipur

Jalali

2000

ANAL. SCI.

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Ketoconazole,-2-(1H-imidazole-1-ylmethyl)-1,3-dioxolan-4-yl]methoxyl]-phenyl]piperazine (I), is a highly effective broad-spectrum antifungal agent which is used to treat a wide variety of superficial and systematic mycoses.1,2 It has an advantage over other imizazole derivatives of producing adequate sustained blood levels following oral administration. Meanwhile, ketoconazole may cause some changes in cytochrome P-450-dependent monooxygenase activities 4,5 as well as in epoxide hydrolase activity. 6 Due to the vital importance of ketoconazole determination in biological fluids and in pharmaceutical preparations, several chromatographic 3,7-11 and spectroscopic [12][13][14][15][16] methods for its quantitative determination have been reported. However, some of these methods need expensive equipment and/or are time consuming.On the other hand, ion-selective membrane electrodes which are selective to a variety of ionic drugs have attracted increasing interest because of their potential use in pharmaceutical analysis. [17][18][19] The inherent advantages of ion-selective electrodes (ISEs) are simplicity, short measurement time, low cost, adequate precision and accuracy, adequate detection limits, wide analytical range, and particularly the ability to measure the activity of various drugs selectively, and in most cases, without prior separation of the drug of interest from the formulation matrix in colored or cloudy samples. These make ISE potentiometry very attractive for pharmaceutical analysis. [20][21][22] In this paper, we describe a simple potentiometric PVC-membrane sensor for the determination of ketoconazole in pharmaceutical preparations and in biological matrices. The membrane used in this electrode was made from liquid-plasticized PVC and was based on a water-insoluble ketoconazole-tetraphenylborate ion pair as an ion-exchanger. Experimental ReagentsAll of the chemicals used in this study were of the highest purity available and were used without further purification, except for vacuum drying over P2O5. Doubly distilled deionized water was used throughout. Reagent-grade ketoconazole as well as tablets and creams containing 200 mg and 2% of the drug, respectively, were obtained from Behvazan pharmaceutical company, Rasht, Iran. Reagent-grade nitrophenyl octyl ether (NPOE), tetrahydrofuran (THF), sodium tetraphenylborate (NaTPB), high relative molecular weight PVC and the nitrate salts of all cations used (all from Merck) were used as received.A working standard solution of 0.05 mol dm -3 ketoconazole was prepared by dissolving 0.2657 g of pure drug in ca. 6 cm 3 of 0.2 mol dm -3 hydrochloric acid and diluting to the mark with water in a 10 cm 3 calibrated volumetric flask. More dilute solutions were prepared by further dilution of appropriate volumes of the standard solution with water.The ion exchanger was prepared by shaking 5.0 cm 3 of a 0.01 mol dm -3 ketoconazole solution with an equal volume of a 0.01 mol dm -3 of sodium tetraphenylborate.The resulting ketoconazole-tetraphenylborate ion-pair precip...

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Section: Resultsmentioning

confidence: 90%

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confidence: 99%

Preparation of a Ketoconazole Ion-Selective Electrode and Its Application to Pharmaceutical Analysis

Shamsipur

Jalali

2000

ANAL. SCI.

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“…Applications to the determination of mercury in hazardous wastes are demonstrated; the results compare favorably with data obtained with cold vapor atomic absorption spectrometry. Silver ions, which seriously interfere with many suggested sensors, 9,10,16,20,21 have little influence on the response of the proposed sensors and the effect of lead ions can be avoided by addition of sulfate ions prior to analysis. …”

Section: Discussionmentioning

confidence: 99%

“…Indirect measurements of mercury with a solid-state membrane sensor involve exchange reactions with copper and silver dithiooxamide and diethyldithiocarbamate followed by measurements of the displaced silver and copper ions with Ag2S and Ag2S/CuS membrane sensors, respectively. 10 The use of PVC matrix membrane sensors for Hg 2+ has received much attention. Many sensing agents have been described, including calixarene derivatives containing thiazole azo group, 11 salicylaldehyde thiosemicarbazone, 12 Schiff's bases, 13 ethyl-2-benzoyl-2-phenylcarbamoyl acetate, 14 2-mercapto-benzothiazole or hexathiacyclooctadecane, 15 dibenzodiazathia-18-crown-6 dione, 16 substituted aza crown ionophores, 17 hexathia-18-crown-6 tetrone, 18 1,3-diphenylthiourea, 19 tetrathia-diazacyclotetradeca-2,9-diene, 20 substituted diaza crown ethers, 21 and p-tert-butyl calix-4-crowns with imine units.…”

Section: Introductionmentioning

confidence: 99%

Mercury(II) Ion-Selective Polymeric Membrane Sensors for Analysis of Mercury in Hazardous Wastes

et al. 2006

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Reagents and chemicalsAll reagents used were of analytical grade; deionized water Two novel potentiometric sensors that are highly selective to Hg 2+ ions are described. These are based on the use of 5,5′-dithio-bis(2-nitrobenzoic acid) (DTNB) and tricyclazole (TCZ) as neutral carriers in plasticized poly(vinyl chloride) membranes. Fast Nernstian responses are obtained for Hg 2+ ions over the concentration ranges 7.0 × 10 -6 -1.0 × 10 -2 and 7.7 × 10 -6 -1.0 × 10 -2 mol l -1 at pH 1.8 -3.3 with lower detection limits of 5.0 × 10 -6 and 5.6 × 10 -6 mol l -1 (∼1 μg ml -1 ) and calibration slopes of 30.0 and 29.7 mV decade -1 with DTNB-and TCZ-based membrane sensors, respectively. Validation of the assay method reveals good performance characteristics, including long life span, good selectivity for Hg 2+ ions over a wide variety of other metal ions, long term response stability, and high reproducibility. Applications for direct determination of mercury in hazardous wastes including dental amalgam, mercury bulbs, and fluorescent lamps give results with good correlation with data obtained using cold vapor atomic absorption spectrometry.

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“…[8][9][10] The increasing use of ion sensors in the fields of environmental, agriculture, industrial and medicinal analysis is putting more and more pressure on analytical chemists to develop new sensors for fast, accurate, reproducible and selective determination of various species. Lead is a trace heavy metal of major interest in environmental protection owing to its cumulative toxicity.…”

Section: Introductionmentioning

confidence: 99%

A New Lead(II)-Selective PVC-Coated Graphite Rod Electrode Based on a Schiff Base Complex

2003

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Membrane sensors for the selective determination of fluorouracil

Cited by 38 publications

References 9 publications

Preparation of a Ketoconazole Ion-Selective Electrode and Its Application to Pharmaceutical Analysis

Preparation of a Ketoconazole Ion-Selective Electrode and Its Application to Pharmaceutical Analysis

Mercury(II) Ion-Selective Polymeric Membrane Sensors for Analysis of Mercury in Hazardous Wastes

A New Lead(II)-Selective PVC-Coated Graphite Rod Electrode Based on a Schiff Base Complex

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