ABSTRACT
Buccal tablets
Diclofenac sodium
Drug release
Mucoadhesion
Mucoadhesive tablets
Release kinetics
ABSTRACT
Objective: To develop and validate the RP-HPLC method and in vitro dissolution study for escitalopram as antidepressant drug and their formulation. Methods: The chromatographic separation was done by using a C-18, 150 mm column and a mobile phase consisting of phosphate buffer (40%) and acetonitrile HPLC grade (60%). Detection was carried out at 211 nm with a flow rate of 1 ml/min with an injection of 20 μl. The method was validated with different parameters such as linearity, precision, accuracy, robustness, and limit of detection (LOD), the limit of quantification (LOQ) according to ICH guidelines. Results: The linear calibration curve was obtained in the concentration range of 0-50 μg/ml and gave an average correlation factor 0.992. The retention time was observed at 2.96 min. The Minimum concentration level at which the analyte can be reliably detected (LOD) and quantified (LOQ) were found to be 0.03 and 0.09 µg/ml, respectively. The relative standard deviation of intra and the inter-day assay was found to be less than 2. The dissolution studies show moderate dissolution (23.4%) after 45 min, but it reaches a plateau after approximately 25 min. Conclusion: This method was found to be simple, rapid and economic with less run time. The validated parameters manifest the method is reliable, linear, accurate and precise as well as robust with minor variations in chromatographic parameters. Therefore, the developed method can be applied for both routine analysis and quality control assay and it could be a very powerful tool to investigate the stability of escitalopram.
ABSTRACT
El propósito de los estudios in vitro es comparar las características de liberación del principio activo contenido en una forma farmacéutica sólida oral mediante la cantidad, o porcentaje de la dosis, disuelta en función del tiempo en condiciones controladas y validadas. Se realizó una comparación de disolución in vitro de flunitrazepam (Rohypnol®, Somnidual® e Inervon®) y de lamotrigina (Lamictal® y Epilepax®). Para los perfiles de disolución de flunitrazepam, una de las marcas comerciales tuvo un perfil de disolución muy diferente a las otras dos marcas. Para el caso de lamotriginano existió diferencia para aquellos pH que se consideran fundamentales para la disolución del comprimido en el tracto gastrointestinal. Los resultados obtenidos de los estudios in vitro son simplemente orientadores, permiten tan solo guiar la puesta en marcha del ensayo de bioequivalencia entre el test evaluado in vitro y la referencia utilizada en el mismo ensayo. No obstante, estos resultados pueden constituirse en un elemento de apoyo a la presunción de bioinequivalencia como causa de un evento adverso (ineficacia o toxicidad) detectado en los programas de farmacovigilancia actualmente en marcha.
Subject(s)
Humans , Anticonvulsants/pharmacokinetics , Flunitrazepam/pharmacokinetics , In Vitro Techniques , Bipolar Disorder/drug therapyABSTRACT
A rapid, economic and robust stability indicating HPLC method was developed and validated to quantify Tenofovir disoproxil Fumarate (TDF), Emtricitabine (EMT) and Nevirapine (NVP) simultaneously at single wavelength (254 nm) in order to assess the in vitro drug release profile from tablet formulations. Chromatographic separation was performed with a gradient elution of samples on a 4.6 mm x 150 mm, 5 μm, Inertsil ODS-2 column with buffered mobile phase containing solvent A (10 Mm ammonium acetate buffer, pH 4.6) and solvent B ( acetonitrile) at a flow rate of 1.0 mL/min). In dissolution studies, the sink condition was optimized based on quantitative solubility of TDF, EMT and NVP standards in different dissolution medium as recommended by USP. The proposed HPLC method and dissolution test condition were validated as per ICH guidelines. The results obtained meet the regulatory criteria thereby confirming that the method is suitable for routine quality control analysis and in vitro dissolution studies.
ABSTRACT
The aim of the present work was to develop and validate a simple, efficient, economical and LC-MS compatible method for the analysis of Terbutaline sulphate in bulk, dosage forms and in dissolution samples of Terbutaline sulphate tablets by reverse phase high pressure liquid chromatography. A C18 reverse phase column (Phenomenex) of 250 x 4.6mm dimensions and 5μm particle size with mobile phase containing 15mM ammonium acetate: methanol (70:30% v/v) was used at isocratic mode binary pump and eluents were monitored at 220nm. The retention time of Terbutaline sulphate was 4.1min and showed a good linearity in the concentration range of 2-10μg/mL with a correlation coefficient >0.999. The validation characteristics included specificity, linearity, and limit of detection, limit of quantification, precision, robustness and stability. Validation acceptance criteria were met in all cases. The percent recoveries ranged between 98-102%, RSD < 2%. The method could be successfully used for the analysis of Terbutaline sulphate in bulk, dosage forms and in dissolution samples of marketed Terbutaline sulphate tablets.
ABSTRACT
This article reports a study of the influence of sodium starch glycolate (SSG) on the dissolution of nimesulide carried in hard gelatin capsules. Some physicochemical parameters of nimesulide were characterized and formulations containing three different contents of SSG were prepared, to compound the hard gelatin capsules of nimesulide. The capsules obtained, as well as the reference drug, were subjected to in vitro dissolution tests. During the maximum pharmacopoeial dissolution time, the amount of drug substance dissolved was determined and the dissolution profile was traced from the amount of drug dissolved in each time interval. The dissolution profiles were compared by the simple Model-Independent Method, by statistical assessment of the dissolution profile data for each time interval and by the dissolution efficiency (DE). The results show that SSG, used as a disintegrant, has a positive influence on the dissolution of nimesulide, facilitating the disintegration of the dosage form, increasing the contact surface of the drug with water and with it the dissolution rate. The N3 capsules, which had the highest content of SSG, 13% (w/w), complied with the pharmacopoeial specification for dissolution tests and the comparative tests of dissolution profiles showed that the N3 capsules exhibited rapid dissolution and an in vitro dissolution profile similar to that of the reference drug. Thus, the N3 capsules can be considered as a pharmaceutical alternative to the reference drug.
O presente trabalho avaliou a influência do Amido Glicolato de Sódio (AGS) na dissolução da nimesulida veiculada em cápsulas gelatinosas duras. Para tanto, foram caracterizados alguns parâmetros físico-químicos da nimesulida; e formulações, contendo diferentes concentrações de AGS, foram preparadas para compor as cápsulas gelatinosas duras de nimesulida. As cápsulas obtidas, bem como o medicamento referência, foram submetidos aos ensaios de dissolução in vitro. Determinou-se, para o tempo de dissolução máximo farmacopeico, a quantidade da substância ativa dissolvida, bem como traçou o perfil de dissolução a partir da quantidade de substância dissolvida em cada intervalo de tempo. A comparação dos perfis de dissolução foi realizada pelo Método Modelo Independente Simples, pela avaliação estatística dos dados dos perfis de dissolução para cada intervalo de tempo e pela Eficiência de Dissolução (ED). Os resultados mostram que o AGS, utilizado como desintegrante, tem características que interferem positivamente na dissolução da nimesulida, facilitando a desintegração da forma farmacêutica, aumentando a superfície de contato do ativo com a água e, com isso, a velocidade de dissolução. As cápsulas N3, que possuem 13% (p/p) de AGS, cumprem com as especificações farmacopeicas para os testes de dissolução, e ensaios comparativos de perfis de dissolução mostram que as cápsulas N3 apresentam dissolução rápida e perfil de dissolução in vitro semelhante ao medicamento referência. Logo, as cápsulas N3 podem ser consideradas como alternativas farmacêuticas aos comprimidos referência.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal , Dissolution , Spectrophotometry, Ultraviolet/methods , Pharmaceutical Preparations , SolubilityABSTRACT
Valsartan (VAL) is a potent, highly selective and orally active antihypertensive drug and is poorly soluble in aqueous fluids, especially in gastric fluids, and its absorption is thus dissolution rate limited. In the present research work an attempt has been made to improve the aqueous solubility of VAL by the recrystallization of VAL from a variety of different organic solvents, and evaluating the recrystallized VAL products for its physicochemical characteristics and in-vitro dissolution properties. The water solubility of methanol (MET), ethanol (ETH), isopropanol (ISP) and acetonitrile (AN) recrystallized products of VAL is significantly higher when compared to untreated VAL. Physicochemical characterization techniques like scanning electron microscopy, differential scanning calorimetry, powder X-RD reveal the change in crystallinity of VAL with recrystallized products and hence the increase in the solubility and superior dissolution properties when compared to the untreated VAL.
ABSTRACT
Introducción: complejos de glicina con los cationes magnesio, manganeso y zinc podrían ser parte de una formulación de un suplemento nutricional que proporcione una adecuada absorción de los metales en el organismo sin generar molestias gastrointestinales. Objetivo: realizar una aproximación a la solubilidad de los complejos de glicina con los cationes magnesio, manganeso y zinc. Métodos: se efectuaron estudios de disolución y análisis de imagen. Se realizó la síntesis y la verificación de formación de los complejos por espectroscopia infrarroja, calorimetría de barrido diferencial, análisis termogravimétrico y difracción de rayos X de polvos. Resultados: se obtuvieron por análisis de imagen los descriptores: circularidad, diámetro de Feret y dimensión fractal; esta última se relacionó con el proceso de disolución en agua, para obtener dos propiedades relacionadas: la dimensión fractal superficial y la dimensión fractal reactiva. Conclusiones: los resultados muestran que el proceso de disolución de los glicinatos, se realiza a través de los poros o grietas de la superficie de las partículas de estos y que son aptos para su empleo en formulaciones nutricionales como fuentes de magnesio, manganeso y zinc.
Introduction: Complexes of glycine and cations magnesium, manganese and zinc, could be included in the formulation of a nutritional supplement that provides adequate absorption of these metals into the body without gastrointestinal disturbances. Objective: to study the solubility of complexes of glycine and cations manganese, zinc and magnesium. Methods: dissolution and image analysis studies were performed. The synthesis and verification of the formation of complexes were carried out by infrared spectroscopy, differential scanning calorimetry, thermal gravimetric analysis, and X-ray diffraction of dust. Results: the image analysis showed some descriptors such as circularity, the Ferret diameter and the fractal dimension. The latter was related to the water dissolution process in order to obtain two associated properties, that is, the surface fractal dimension and the reactive fractal dimension, Conclusions: these results showed that the dissolution of glycinates occurs through the pores or cracks found in their particle surfaces and that these complexes are suitable for use in nutritional formulations as sources of magnesium, manganese and zinc.