Preparation, characterization and evaluation of fast-dissolving silibinin-enriched silymarin [SES]

The hepato-protective activity of silymarin is well demonstrated. However, silymarin is not a single component, but a mixture of silydianin, silychristin and silibinin. Silibinin is the least soluble and the most active component of silymarin. Accordingly, as silibinin content of silymarin increases, its activity is expected to increase. These were the objectives of the study i. e to prepare silibinin enriched silymarin [SES] and enhance its dissolution by preparing its adsorbates and co-adsorbates with Florite. Silibinin enriched silymarin was prepared by extracting the water soluble components of silymarin using water. The silibinin content of the SES was evaluated using HPLC method of assay. The fast dissolving SES systems were characterized using differential scanning calormetry, x-ray diffractometry and infra-red spectroscopy. The obtained results indicated the compatibility of Florite with SES. The biological activity of SES systems was evaluated in rats using paracetamol as a hepatotoxic agent and compared to that of silibinin alone. The results showed that SES-co-adsorbate was more efficient in lowering the serum level of the specific liver enzymes [ALT and AST] than silibinin alone

Controllbd-release prednisolone poly [DL-lactide] microspheres: impact of formulation parameters, characterization and release mechanism

The steroidal drug prednisolone was encapsulated into microspheres using the biodegradable polymer poly [DL-lactide] using emulsion-solvent evaporation method. The produced microspheres were characterized using scanning electron microscopy, X-ray diffractometery, FT-IR spectroscopy, DSC, and laser light diffraction. The morphology, particle size distribution, encapsulation efficiency [EE%], and drug release showed marked dependence upon formulation parameters viz. initial polymer concentration, surfactant concentration, drug-to-polymer ratio, and volume of the external aqueous phase. The effect of the addition of hydrophilic additives such as PVP or PEG 8000 was also investigated. The encapsulation efficiency percent and the mean particle size were increased by increasing the initial polymer concentration and drug polymer ratio. On the other hand, increasing the surfactant concentration resulted in decreasing the mean particle size and increasing the drug release from the microspheres. The probable mechanism of drug release was estimated and found to be via diffusion through channels and/or pores present within the polymeric matrix. Release data of almost all formulae fitted Higuchi's planar model better than spherical model. This finding could be due to the small extent of drug release [- 40%], or the presence of a large fraction of the encapsulated drug nearby the surface of the microspheres

Formulation and evaluation of hydrochlorothiazide liquisolid tablets

The technique of liquisolid preparations was used to formulate hydrochlorothiazide, a model drug, in tablet form. Drug solution in peg200 was blended with different common tablet excipients such as Avicel, Aerosil, Calcium phosphate, Magnesium oxide, and Magnesium carbonate. The drug admixtures were directly compressed into tablets. The dissolution rates of the liquisolid tablets were determined according to USP basket method. The obtained dissolution profiles were compared to that of a reference tablet, made by simple trituration of drug powder with avicel, and a commercial product. The results showed that, generally, liquisolid tablets present a significantly higher dissolution rate. A