RESUMO
The present work describes a quantitative thin layer procedure for estimating primidone, clorazepate dipotassium and chlorzoxazone in bulk powders and in dosage forms, each in the presence of its degradation product. The method consists of dissolving the drug in ethanol (for primidone), or methanol (for clorazepate dipotassium and chlorzoxazone) and then spotting this solution on a thin layer of silica gel G254. Quantitation is achieved by comparing the areas under the peaks obtained from scanning the thin layer chromatographic plates in a spectrodensitometer.
Assuntos
Anticonvulsivantes/análise , Clorzoxazona/análise , Clorazepato Dipotássico/análise , Primidona/análise , Cápsulas/normas , Densitometria/métodos , Densitometria/normas , Reprodutibilidade dos Testes , Comprimidos/normasRESUMO
Direct bromometric titration of carbimazole using N-bromosuccinimide (NBS) in the presence of methyl red as indicator and three indirect titrations using NBS, potassium bromate and dibromohydantoin (DBH) are developed. The direct procedure can be adopted for quantities of carbimazole ranging from 2-12 mg with mean accuracies of 100.2 +/- 0.5. The indirect procedures can be used for quantities of the drug ranging from 1-6 mg using NBS and DBH and 2-16 mg using potassium bromate with mean accuracies of 100.11 +/- 0.3, 100.49 +/- 0.31 and 100.26 +/- 0.51 respectively. The proposed procedures have been successfully applied for the analysis of the drug in tablet form and their validity has been checked using the standard addition technique. The reaction products were separated by TLC methods and their structure was elucidated using IR and NMR spectroscopy. The stoichiometry and the possible pathways of the reaction were postulated and presented.
RESUMO
A new direct, simple, and sensitive spectrofluorometric method is described for the assay of pindolol and its tablets at room temperature, using ethanol (96% v/v) as solvent. The drug exhibits intrinsic fluorescence. Working wavelengths are 263 nm for excitation and 305 nm for emission. The calibration curve is linear in the range 1.0 X 10(-7) to 1.5 X 10(-6)M pindolol.
Assuntos
Pindolol/análise , Espectrometria de Fluorescência , Comprimidos/análiseAssuntos
Propanolaminas/análise , Fenômenos Químicos , Química , Nadolol , Oxirredução , Ácido Periódico , Pós/análise , Comprimidos/análise , TemperaturaRESUMO
2-(2,6-Dichloroanilino)-2-imidazoline hydrochloride (clonidine, Catapres) reacts with sodium nitroprusside in presence of sodium hydroxide, and on treatment with saturated boric acid it gives a violet colour measurable at 570 nm. The effect of pH, time, concentration of sodium nitroprusside and the type of acid used was studied. This colour is used to develop a colorimetric method for the determination of clonidine in its pharmaceutical preparations. The method can be adopted by quantities ranging from 200 to 1500 microgram with 100% +/- 1.68 accuracy.
Assuntos
Clonidina/análise , Fenômenos Químicos , Química , Colorimetria/métodos , Espectrofotometria , Comprimidos/análise , TemperaturaRESUMO
An indirect complexometric method is described for the determination of piperazine alone or in its pharmaceutical preparations. The method involves treatment of the aqueous solution of piperazine with carbon disulphide, ammonia solution and a known excess of cupric acetate, filtration of the formed precipitate and determination of the excess cupric acetate with EDTA using PAR as indicator.