Dissolution rate

Mebendazole is a poorly soluble, highly permeable drug and the rate of its oral absorption is often controlled by the dissolution rate in the gastrointestinal. The poor dissolution rate of water-insoluble drugs is still a major problem confronting the pharmaceutical industry. There are several techniques to enhance the dissolution of poorly soluble drugs. Among them, the technique of Liquisolid compacts is a promising technique towards such a novel aim. In this study, the dissolution behaviour of mebendazole from liquisolid compacts was investigated in 0.1 N HCl. Liquisolid compacts were prepared by using PEG 400 as the liquid vehicle or non-volatile solvent. Avicel PH 102 as absorbing carrier and Aerosil 200 as adsorbing coating material. The ratio of carrier to coating powder material were kept different in formulations. The prepared liquisolid compacts were evaluated for their micromeritic properties and possible excipients interactions. The tableting properties were falling within acceptable limits. The in vitro dissolution study confirmed increase in drug release from liquisolid compacts compared to marketed preparation. This was due to an increase in wetting properties and surface of drug available for dissolution.

The objective was to enhance the solubility and dissolution rate of Artemether poorly water soluble antimalarial, by the preparation of solid dispersion (SD) granules. The dispersion granules were prepared using a hot melt granulation technique which involved the preparation of a homogenous dispersion of ARTM in surfactant melt, followed by its adsorption onto the surface of AEROPERL® 300 Pharma, an inert absorbent using the solvent evaporation method. The dispersion granules were characterized for their in-vitro dissolution rate, moisture content and flow properties. The formulation was further characterized by FTIR,DSC, XRD and SEM analysis. FTIR spectrum revealed some drug excipient interactions. DSC and XRD data indicated the retention of amorphous form of ARTM. SEM confirmed the homogeneity and surface adsorption of the ARTM-Lutrol F127 or ARTM-Lutrol F68 melt on AEROPERL® 300 Pharma leading to an enhanced surface area and thus the dissolution rate. The optimized dispersion granules were filled inside the capsules and evaluated. The in-vitro dissolution rate of these capsules was significantly better in comparison with pure drug. Physical characterisation enabled us to understand the effects of formulation variables on the dispersion granules of ARTM.