Utilization of carbon disulphide for the analytical determination of betahistine hydrochloride and captopril in their pharmaceutical preparations

Walily, Abdel Fattah M. El; Razak, Omayma Abdel; Belal, Saied; Bakry, Rania

doi:10.1016/s0731-7085(99)00159-4

Cited by 36 publications

(13 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In order to assure the quality of CPT containing pharmaceutical formulations, several methods have been developed for its determination, including batch fl uorimetry [3], chemiluminescence [4 -7], AAS [8,9], high-performance liquid chromatography (HPLC) [10 -17], GC [18], differential pulse polarography [19], amperometry [20 -22], volumetric titration [23], potentiometric titration [24 -28], capillary electropho-Artigo Article Artigo Article resis [29], conductometry [30], coulometry [31], voltammetry [32] and potentiometry [33].…”

Section: N Cooh Co Hs Chmentioning

confidence: 99%

A simple spectrophotometric method for the determination of captopril in pharmaceutical preparations using ammonium molybdate

Ribeiro¹,

Pezza

2010

Eclet. Quím.

View full text Add to dashboard Cite

A simple, rapid and sensitive spectrophotometric method for the determination of captopril (CPT) in pharmaceutical formulations is proposed. This method is based on the reduction reaction of ammonium molybdate, in the presence of sulphuric acid, for the group thiol of CPT, producing a green compound (λ max 407 nm). Beer's law is obeyed in a concentration range of 4.60 x 10 -4 -1.84 x 10 -3 mol l -1 of CPT with an excellent correlation coefficient (r = 0.9995). The limit of detection and limit of quantification were 7.31 x 10 -6 e 2.43 x 10 -5 mol l -1 of CPT, respectively. The proposed method was successfully applied to the determination of CPT in commercial brands of pharmaceuticals. No interferences were observed from the common excipients in the formulations. The results obtained by the proposed method were favorably compared with those given by the official reported method at 95 % confidence level.

show abstract

Section: N Cooh Co Hs Chmentioning

confidence: 99%

A simple spectrophotometric method for the determination of captopril in pharmaceutical preparations using ammonium molybdate

Ribeiro¹,

Pezza

2010

Eclet. Quím.

View full text Add to dashboard Cite

show abstract

“…11,13 The official methods for its determination are based on volumetry or chromatography, 14 even though several alternative procedures have been reported in the literature, employing fluorimetry, 15 spectrophotometry, 13,14,16 chemiluminescence, 17 potentiometry 18 and indirect atomic absorption spectrometry. 19 These methodologies are usually time consuming, making the construction of dissolution profiles for solid pharmaceutical forms unfeasible. 20 The main goal of this work was to develop a multicommuted flow-based procedure for captopril determination to construct dissolution curves.…”

Section: Introductionmentioning

confidence: 99%

A multicommuted flow system for dissolution studies of Captopril in pharmaceutical preparations

Sanchez

Rocha

Melchert

et al. 2011

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

Um procedimento analítico em sistema de análises em fluxo com multicomutação é proposto para a determinação de captopril e construção de curvas de dissolução de medicamentos. O método é baseado na reação do fármaco com Cu(II), com posterior complexação de Cu(I) com 4,4'-dicarboxi-2,2'-biquinolina (BQA) e detecção espectrofotométrica. Foi observada resposta linear entre 25 e 300 μmol L -1 captopril, com limite de detecção de 7 μmol L -1 (99,7% de confiança). O coeficiente de variação (n = 20) e a frequência de amostragem foram 2,2% e 47 determinações por hora, respectivamente, com consumo de 290 μg de BQA e geração de 3,6 mL de resíduo por determinação. Os resultados para 7 amostras de preparações farmacêuticas concordaram com os obtidos pelo procedimento volumétrico de referência com 95% de confiança. Perfis de dissolução obtidos com um aparato construído no laboratório foram concordantes com os relatados na literatura, com coeficiente de variação de 1,8% para três replicatas do produto de referência.A flow-based analytical procedure exploiting multicommutation is proposed for captopril determination and the construction of dissolution curves. The procedure is based on the redox reaction between Cu(II) and the drug with the subsequent complexation of Cu(I) with 4,4'-dicarboxy-2,2'-bichinoline (BCA) and spectrophotometric detection. A linear response was observed between 25 and 300 μmol L -1 captopril and the detection limit was estimated as 7 μmol L -1 (99.7% confidence level). The coefficient of variation (n = 20) and sampling rate were 2.2% and 47 determinations per hour, respectively, consuming 290 μg of BCA and generating 3.6 mL of waste per determination. The results for seven pharmaceutical samples agreed with those obtained by the reference volumetric procedure at the 95% confidence level. The dissolution profiles attained with a lab-made dissolution apparatus agreed with those reported in the literature, with a coefficient of variation of 1.8% for three replicates of the reference product.

show abstract

“…Various instrumental methods have been developed for the determination of captopril including HPLC, [8][9][10][11][12][13][14][15] spectrophotometry, 7,[16][17][18][19] fluorimetry, 20,21 capillary electrophoresis 22 and chemiluminescence methods. 23 But all of the reported methods suffer from many interferences such as ascorbic acid, Fe 2+ , Fe 3+ , NO 2 -and/or do not have good limit of detection (>18 nmol L -1 ).…”

Section: Introductionmentioning

confidence: 99%

Simultaneous determination of captopril and thioguanine in pharmaceutical compounds and blood using cathodic adsorptive stripping voltammetry

Ensafi¹,

Hajian²

2008

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

Apresentamos um procedimento altamente seletivo e sensível para a determinação simultânea de captopril e de tioguanina baseado em processo de redissolução catódica adsortiva dos complexos de Cu(I)-captopril e de Cu(I)-tioguanina em um eletrodo gotejante de mercúrio. Captopril e tioguanina foram pré-concentrados na superfície da gota do eletrodo de mercúrio usando Cu(II) como sensor e tempo de acumulação igual a 90 s. Em seguida, os complexos pré-concentrados foram analisados por voltametria adsortiva de pulso diferencial catódica. O efeito de vários parâmetros na sensibilidade, tais como, pH, concentração de cobre, potencial de acumulação, tempo de acumulação e velocidade de varredura, na sensibilidade do método foram estudados. As condições ótimas para a determinação simultânea de captopril e de tioguanina foram: pH = 3,5, concentração de cobre(II) = 45,0 ng mL -1 , potencial de acumulação = -0,10 V e velocidade de varredura = 60 mV s -1 . Nas condições ótimas e tempo de acumulação igual a 90 s, os picos de corrente medidos em torno de -0,15 V e -0,40 V (vs. Ag/AgCl) foram proporcionais às concentrações de tioguanina e de captopril nas faixas de 0,15-180 e 0,5-100 nmol L -1 . Os limites de detecção para tioguanina e captopril foram 0,08 e 0,3 nmol L -1 , respectivamente. Os desvios padrões relativos para cinco replicatas de 20,0 nmol L -1 de captopril e de tioguanina foram 2,5% e 2,1%. O método para a determinação de captopril e de tioguanina foi testado em amostras de misturas sintéticas, farmacêuticas e em soro humano, apresentando resultados satisfatórios.A reliable, highly selective and sensitive procedure is presented for simultaneous determination of captopril and thioguanine based on cathodic adsorptive stripping of Cu(I)-captopril and Cu(I)-thioguanine complexes on a hanging mercury drop electrode. Captopril and thioguanine were preconcentrated onto the surface of hanging mercury drop electrode using Cu(II) as a suitable probe, with accumulation time of 90 s. Then the preconcentrated complexes were analyzed by cathodic stripping differential pulse voltammetry. The effect of various parameters such as pH, concentration of copper, accumulation potential, accumulation time and scan rate on the sensitivity were studied. The optimum conditions for simultaneous determination of captopril and thioguanine include pH=3.5, 45.0 ng mL -1 copper(II) concentration, accumulation potential of -0.10 V and scan rate of 60 mV s -1 . Under the optimum conditions and for an accumulation time of 90 s, the measured peak currents at about -0.15 V and -0.40 V (vs. Ag/AgCl) are proportional to the concentrations of thioguanine and captopril over the ranges of 0.15-180 and 0.5-100 nmol L -1 , respectively. The limits of detection are 0.08 and 0.3 nmol L -1 for thioguanine and captopril, respectively. The relative standard deviations for five replicate analyses of 20.0 nmol L -1 captopril and thioguanine are 2.5% and 2.1%, respectively. The method was applied to the determination of captopril and thioguanine in synthetic mixed sa...

show abstract

Utilization of carbon disulphide for the analytical determination of betahistine hydrochloride and captopril in their pharmaceutical preparations

Cited by 36 publications

References 13 publications

A simple spectrophotometric method for the determination of captopril in pharmaceutical preparations using ammonium molybdate

A simple spectrophotometric method for the determination of captopril in pharmaceutical preparations using ammonium molybdate

A multicommuted flow system for dissolution studies of Captopril in pharmaceutical preparations

Simultaneous determination of captopril and thioguanine in pharmaceutical compounds and blood using cathodic adsorptive stripping voltammetry

Contact Info

Product

Resources

About