Formulation, Evaluation and Optimization of Fast Dissolving Tablets Containing Amlodipine Besylate by Sublimation Method

The objective of this research was to formulate fast dissolving tablet of amlodipine besylate for rapid action. Sublimation method was adapted to prepare the tablets by using a 23 full factorial design. FT-IR and D.T.A studies revealed that there was no physico-chemical interaction between amlodipine besylate and other excipients. All formulations are evaluated for pre-compression and post-compression parameters, wetting time, water absorption ratio. The results obtained showed that the quantity of starch potato, sodium starch glycolate, camphor significantly affect response variables. The results indicate that the optimized tablet formulation provides a short DT of 8 sec with sufficient crushing strength and acceptable friability. Stability studies of optimized formulation revealed that formulation is stable(AU)

Development of Gastro Retentive Drug Delivery System of Cephalexin by using Factorial Design

The objective of this research work was to formulate and optimize the floating drug delivery system containing cephalexin using 23 factorial design. Floating tablets were prepared by direct compression method incorporating HPMC K4M, xanthan gum, guar gum, sodium bicarbonate and tartaric acid as gas generating agent. The influence of independent variables like, polymer: polymer ratio, polymer type and tartaric acid on floating lag time and cephalexin release profile were studied. The diffusion exponent (n) of Krosmeyer Peppas for optimized formulation was found to be 0.635 which indicates the mechanism of drug release was anomalous transport. Floating lag time of optimized formulation was 1.50 min and remained buoyant for 24 hrs. Optimized formulation was checked for stability at 40ºC / 75% RH which was found to be stable. Scanning electron microscopy study revealed gel formation. FT-IR studies revealed that there was no chemical interaction between cephalexin and other excipients(AU)

Caracterización fisicoquímica de los complejos de hidroxietil-Beta-ciclodextrina y Beta-ciclodextrina de rifampicina / Physicochemical characterization of Beta-cyclodextrin and hydroxy ethyl Beta-cyclodextrin complexes of rifampicin

Se realizó un ensayo con el objetivo de optimizar la administración oral de rifampicina mediante la formación decomplejos de inclusión con ciclodextrinas, incluida la Beta-ciclodextrina (Beta-CD) y la hidroxietil-Beta-ciclodextrina (HEBeta-CD). El objetivo del estudio era incrementar la solubilidad y estabilidad de la rifampicina mediante la formaciónde complejos, y evaluar el efecto de la ciclodextrina en el tratamiento de la tuberculosis. Los estudios de solubilidadde fase mostraron que seguía una curva de solubilidad de tipo A y que la pendiente de la línea es inferior a uno,indicando la presencia de fármaco y agente aglutinante en una fracción molar de 1:1. Los complejos de ciclodextrinase prepararon mediante métodos de amasado (AM) y de disolvente común (DC). Las mezclas físicas también se prepararonen la misma proporción. En el caso de los complejos de Beta-CD, se observó una solubilidad dos veces mayoren el complejo preparado mediante disolvente común. Una espectometría infrarroja por transformada de Fourier(FTIR) confi rmó la formación de un complejo con (4-metil-1-piperazinil)-imino-metil de rifampicina de cadena lateral.La formación del complejo se confi rmó mediante estudios de difracción de rayos-x de polvo, microscopía electrónicade barrido (MEB) y calorimetría diferencial de barrido (CDB). Se demostró que la actividad antituberculosa in vitrode la rifampicina se vio mejorada en el caso de todos los complejos indicados mediante una reducción a la mitadde la concentración inhibitoria mínima (CIM) de rifampicina. La formación de complejos de inclusión con Beta-CD ehidroxietil-Beta-ciclodextrina mejoró sus propiedades fi sicoquímicas y su actividad antituberculosa in vitro

An attempt was made to optimize the oral delivery of rifampicin by formation of inclusion complexes with cyclodextrinsincluding Beta-Cyclodextrin (Beta-CD), and hydroxy-ethyl-Beta-cyclodextrin (HEBeta-CD). The aim of the study was to increase thesolubility, stability of rifampicin by way of complexation and to evaluate the effect of cyclodextrin on its anti-tubercularactivity. The phase solubility studies showed that it followed Type-AL solubility curve and the slope of the line is lessthan one, indicating 1:1 molar ratio of drug to complexing agent. Cyclodextrin complexes were prepared by kneading(KN) and common solvent (CS) methods. The physical mixtures (PM) were also prepared in the same ratio. In case ofBeta-CD complexes, a 2 fold increase in solubility was observed with CS complex. Formation of complex with side chain4-methyl piperazin-1-ylimino-methyl of rifampicin was confi rmed by FTIR. Formation of complex was confi rmed by DSC,SEM, and powder x-ray diffraction studies. In vitro anti-tubercular activity of rifampicin was found to be enhanced in case of all the complexes indicated by a reduction in MIC of rifampicin to half. Inclusion complexation with Beta-CDand hydroxy ethyl Beta-cyclodextrin improved its physico-chemical properties and in vitro anti-tubercular activity

Development of three layered buccal compact containing metoprolol tartrate by statistical optimization technique.

The objective of this work to evaluate the effect of formulation variables on release properties and bioadhesive strength in development of three layered buccal compact containing highly water-soluble drug metoprolol tartrate (MT) by statistical optimization technique. Formulations were prepared based on rotatable central composite design with peripheral polymer ratio (carbopol 934P: HPMC 4KM) and core polymer ratio (HPMC 4KM: sodium alginate) as two independent formulation variables. The three layered buccal compact comprises a peripheral layer, core layer and backing layer. Four dependent (response) variables were considered: bioadhesion force, percentage MT release at 8 h, T50% (time taken to release 50% of drug) and release exponent (n). The release profile data was subjected to curve fitting analysis for describing the release mechanism of MT from three layered buccal compact. The main effects and interaction terms was quantitatively evaluated by quadratic model. The decrease in MT release was observed with an increase in both the formulation variables and as the carbopol: HPMC ratio increases the bioadhesive strength also increases. The desirability function was used to optimize the response variables, each having a different target and the observed responses were highly agreed with experimental values. The results demonstrate the feasibility of the model in the development of three layered buccal compact containing highly water-soluble drug MT.