Solid dispersion.

The aim of the study was to improve the solubility of aceclofenac, which is poorly water soluble drug belongs to BCS class-II. Aceclofenac appears to be particularly well tolerated among the NSAIDs, with a lower incidence of gastrointestinal adverse effects. For poorly soluble orally administered drugs, the rate of absorption is often controlled by the rate of dissolution. To improve the solubility of drug by solid dispersions were prepared with different methods like physical mixture, kneading method and solvent evaporation method with various carriers like poloxamer188, poloxamer407 and PEG 6000 in different ratios from 1:1 to 1:5. The prepared formulations were evaluated for physicochemical characteristics, characterized by differential scanning calorimetry (DSC), X-ray diffraction (XRD), in-vitro dissolution studies and saturation solubility. Based on the evaluation parameters poloxamer407 in ratio of 1:5 through solvent evaporation method was optimized and formulated into tablets by direct compression method. These tablets showed a higher in-vitro dissolution drug release which is 99.62% in 30 minutes when compared with pure drug which showed 26.62% in 60 minutes, whereas marketed tablet (Hifenac) shows 99.64±0.10% in 40 minutes. Hence it was concluded that solid dispersion of aceclofenac drug by using polaxamer 407 with solvent evaporation method enhances solubility, absorption rate and increase bioavailability of the aceclofenac drug.

Drugs belonging to BCS class II, low solubility and high permeability; undergo dissolution-rate limited gastrointestinal absorption. Glimepiride is one of the famous drugs belonging to BCS class II. Its poor aqueous solubility usually causes poor dissolution and unpredicted bioavailability. Hence, formulation techniques that accelerate drug dissolution can guarantee a parallel improvement in bioavailability. Now a days different techniques are available to enhance the solubility of drug like co-solvent, solid dispersion, chemical modification of drug, liquisolid technique etc. One of the favorable strategy to improve the solubility and hence bioavailability of poorly water soluble drugs is theformulation of solid dispersion. The solid dispersion may be prepared by solvent evaporation method, melting method, melt solvent method, kneading method, co-grinding method, co-precipitation method, modified solvent evaporation method, spray drying, gel entrapment techniqueand co-precipitation with supercritical fluid. This review article comprises of the research materialized in the field of solubility and dissolution enhancement of glimepiride.

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.