RESUMEN
The present study focused to develop rapid, accurate and sensitive reversed-phase high pressure liquid chromatography method for the quantification of esomeprazole (ESO) magnesium in rabbit plasma. Chromatographic separation was achieved isocratically on a reversed-phase C,, column using simple mobile phase consisting of of methanol : acetonitrile: 0.05 M phosphate buffer, pH 7 adjusted with potassium hydroxide (45 : 10 : 45, v/v/v) at a flow rate of 1.0 mL/min and UV detection at 302 nm. The method was validated for system suitability, linearity, precision, accuracy, stability, robustness, LOD and LOQ. The described method stated good linearity over the range of 0.01 to 2.5 pg/mL (r = 0.999). The extraction recovery of esomeprazole was more than 95.3%. The method was precise with relative standard deviation < 1% with more than 90% accuracy and limit of quantification 0.0309 µg/mL. The freeze thaw stability studies indicated that the rabbit plasma samples containing esomeprazole could be stored in freezer at -20°C and handled under normal laboratory conditions without significant loss of drug. In conclusion, the developed method is simple, cost effective and reproducible, with improved sensitivity and running time of analysis.
Asunto(s)
Cromatografía Líquida de Alta Presión , Cromatografía de Fase Inversa , Monitoreo de Drogas/métodos , Esomeprazol/sangre , Inhibidores de la Bomba de Protones/sangre , Acetonitrilos/química , Animales , Tampones (Química) , Frío , Estabilidad de Medicamentos , Congelación , Concentración de Iones de Hidrógeno , Hidróxidos/química , Límite de Detección , Modelos Lineales , Metanol/química , Compuestos de Potasio/química , Conejos , Reproducibilidad de los Resultados , Solventes/química , Espectrofotometría UltravioletaRESUMEN
Chondroitin sulfate and sodium alginate were incorporated in different ratios to prepare glutaraldehyde (GA) crosslinked microspheres by water-in-oil emulsion crosslinking method for delivery of 5-flurouracil (5-FU) to colon. Chemical interaction, surface morphology, thermal degradability, crystallinity evaluation, elemental analysis and drug release results were computed by using FTIR, SEM, DSC and TGA, PXRD, EXD and dissolution studies at pH 1.2, pH 6.8 and pH 7.4, respectively. Results revealed an acetal ring formation, non-porous surfaces, stability up to 450 degrees C with mass loss of 84.31%, variation in carbon and oxygen contents and targeted release at pH 7.4. Different kinetic models were applied on release studies i.e., zero order, first order, Higuchi and Korsmeyer-Peppas. Higuchi model was declared as best fit model based on r2 value (0.99) and mechanism of release was non-Fickian diffusion. A potential approach for colonic delivery of 5-FU was successfully developed.
Asunto(s)
Alginatos/química , Antimetabolitos Antineoplásicos/química , Sulfatos de Condroitina/química , Portadores de Fármacos , Fluorouracilo/química , Administración Oral , Antimetabolitos Antineoplásicos/administración & dosificación , Rastreo Diferencial de Calorimetría , Química Farmacéutica , Colon , Reactivos de Enlaces Cruzados/química , Cristalografía por Rayos X , Preparaciones de Acción Retardada , Fluorouracilo/administración & dosificación , Ácido Glucurónico/química , Glutaral/química , Ácidos Hexurónicos/química , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Microesferas , Modelos Químicos , Porosidad , Difracción de Polvo , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Tecnología Farmacéutica/métodos , TermogravimetríaRESUMEN
In this study, a series of pH sensitive microgels (MGs) were prepared by modified free radical suspension polymerization of 2-hydroxyethyl methacrylate (HEMA) and itaconic acid (IA), using ethylene glycol dimethacrylate (EGDMA) as crosslinker. Equilibrium swelling technique was employed for esomeprazole magnesium trihydrate (EMT) loading. Prepared microgels were characterized through Fourier transforms infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering technique (DLS), scanning electron microscopy (SEM), equilibrium swelling and in vitro drug release kinetics. FTIR and TGA confirmed the formation of copolymeric p(HEMA-co-IA) network. SEM and DLS revealed smooth, round and uniformly distributed microspheres with particle size up to 10 µm. Developed microgels found to be pH responsive in nature. All the formulations (HIDI - HID5) followed Higuchi model with non-Fickian diffusion mechanism of drug release. It was concluded that p(HEMA-co-IA) microgels have potential to be used as drug carriers for site specific and controlled drug delivery.