RESUMO
A new stability-indicating RP-HPLC assay method was developed and validated for quantitative determination of loteprednol etabonate in bulk drugs and in ophthalmic suspensions in the presence of degradation products generated from forced degradation studies. The system consisted of Agilent Technologies Zorbax Eclipse XDB-Phenyl 5 µm 4.6 × 250 mm, and detection was performed at 244 nm. The mobile phase consisted of water-acetonitrile-acetic acid (34.5:65.0:0.5, v/v/v) run at a flow rate of 1 mL/min and maintained at room temperature. The calibration curve was linear from 30 to 70 µg/mL with r > 0.999. Accuracy (mean recovery 100.78%) and precision were found to be satisfactory. Stress conditions including acid and alkali hydrolysis, water stress, oxidation, photolysis and heat were applied. The degradation products did not interfere with the detection of loteprednol etabonate, thus the method can be considered as a stability-indicating method. The proposed method can be used for quality control assay of loteprednol etabonate in bulk drug and in ophthalmic suspensions and for stability studies as a result of the ability of the method to separate loteprednol etabonate from its degradation products and excipients.
Assuntos
Androstadienos/química , Cromatografia Líquida de Alta Pressão/métodos , Soluções Oftálmicas/química , Cromatografia de Fase Reversa/métodos , Estabilidade de Medicamentos , Etabonato de Loteprednol , Controle de QualidadeRESUMO
Simple, sensitive, and economical simultaneous volumetric and HPLC methods for the determination of pridinol mesylate in raw material have been developed. The volumetric method is based on the reaction of pridinol with sodium lauryl sulphate in diluted sulphuric acid. Dimethyl yellow was used as indicator to detect the end point of the titration in aqueous/organic layer. The HPLC method for the determination of pridinol mesylate employs a reverse phase C18 column at ambient temperature with a mobile phase consisting of acetonitrile: 0.05 M potassium dihydrogen phosphate, pH adjusted to 5.0 (1 : 2, v/v). The flow rate was 0.8 mL/min. Quantitation was achieved with UV detection at 258 nm based on peak area. Both methods were found to be suitable for the quality control of pridinol mesylate in raw material.
RESUMO
An isocratic HPLC method was developed and validated for the quantitation of methocarbamol in the presence of its degradation products. Quantitation was achieved using a reversed-phase C18 column at ambient temperature with mobile phase consisting of methanol-water-tetrahydrofuran (25 + 65 + 10, v/v). The flow rate was 0.9 mL/min. The detection was by UV light at 274 nm. The proposed method was validated for selectivity, precision, linearity, and accuracy. The assay method was found to be linear from 159.0 to 793.2 microg/mL (3.2 to 15.9 microg injected). All validation parameters were within the acceptable range. The developed method was successfully applied to estimate the amount of methocarbamol in a veterinary injection.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Metocarbamol/análise , Drogas Veterinárias/análise , Técnicas de Química Analítica/métodos , Química Farmacêutica/métodos , Furanos/análise , Metanol/química , Modelos Químicos , Relaxantes Musculares Centrais/análise , Reprodutibilidade dos Testes , Raios Ultravioleta , Água/químicaRESUMO
An accurate, simple, and reproducible liquid chromatographic method was developed and validated for the determination of tacrolimus in capsules. The analysis is performed at room temperature on a reversed-phase C18 column with UV detection at 210 nm. The mobile phase is methanol-water (90 + 10) at a constant flow rate of 0.8 mL/min. The method was validated in terms of linearity, precision, accuracy, and specificity by forced decomposition of tacrolimus, using acid, base, water, hydrogen peroxide, heat, and light. The response was linear in the range of 0.09-0.24 mg/mL (r2 = 0.9997). The relative standard deviation values for intra- and interday precision studies were 1.28 and 2.91%, respectively. Recoveries ranged from 98.06 to 102.52%.
Assuntos
Imunossupressores/análise , Tacrolimo/análise , Cromatografia Líquida , Formas de Dosagem , Indicadores e Reagentes , Padrões de Referência , Reprodutibilidade dos Testes , Soluções , Espectrofotometria UltravioletaRESUMO
An accurate, simple, reproducible, and sensible liquid chromatographic method was developed and validated for the determination of chlorpheniramine maleate and dexamethasone in a tablet formulation. The analysis was performed at room temperature on a reversed-phase C18 column with UV detection at 254 nm. The mobile phase consisted of 7.5 mM monobasic potassium phosphate in methanol-water (62.5 + 37.5) at a constant flow rate of 1 mL/min. The method was validated in terms of linearity, precision, accuracy, and specificity by forced decomposition of chlorpheniramine maleate and dexamethasone initiated by using acid, base, water, hydrogen peroxide, heat, and light. The response was linear in the ranges of 0.04-0.12 and 0.006-0.016 mg/mL for chlorpheniramine maleate (r2 = 0.9999) and dexamethasone (r2 = 0.9994), respectively. The relative standard deviation values for intra- and interday precision studies were 2.39 and 2.02, respectively, for chlorpheniramine maleate and 2.39 and 1.25, respectively, for dexamethasone. Recoveries ranged from 95.07 to 101.95% for chlorpheniramine maleate and from 97.75 to 102.10% for dexamethasone.