Nirmal Shah

The present research work focuses on improving the bioavailability of the anti osteoporotic drug Risedronate Sodium. This drug belongs to BCS class III which implies that it is permeability rate limited. Hence an attempt was made to reduce the particle size to nano dimensions using ionotropic gelation technique. In this technique, chitosan was used as the polymer and sodium Tri poly Phosphate was used as the cross linking agent. The resulting nanoparticles were optimized using 32 full factorial design and characterized for their entrapment efficiency, percent yield, in vitro diffusion studies. The particle size and zeta potential was found out and surface morphology was studied using Scanning electron microscopy. The in vivo studies clearly showed a marked improvement in the bioavailability of the nanoparticles as compared to the plain drug suspension.

Quetiapine Fumarate is a antipsychotic agent indicated for treatment of Schizophrenia and Bipolar disorder. Quetiapine Fumarate is BCS Class II drug which is  poorly water soluble and may show dissolution limited absorption. Hence to improve dissolution rate and bioavailability, Solid dispersion of Quetiapine Fumarate by Solvent Evaporation method were prepared using 1:1, 1:2, 1:3, 1:4 and 1:5 ratios of Quetiapine Fumarate and Polyvinyl Pyrrolidone K30(PVP K30). The solid dispersion (SD) was characterized for physical appearance, solubility, FTIR, DSC, XRD studies and in vitro dissolution studies. FTIR study revealed that there was no drug-carrier chemical interaction in Solid dispersion. DSC studies revealed that, the peak observed for the melting of Quetiapine Fumarate is found to be absent in SD with PVP K30 carrier. XRD studies suggested that there has been a large change in the nature of Quetiapine Fumarate in the solid dispersion. Solubility of Quetiapine Fumarate from SD increased in distilled water. The drug content was found to be high and uniformly distributed in the formulation. The in vitro dissolution studies were carried using USP type II (paddle) type dissolution apparatus. The prepared Solid dispersion showed marked increase in the dissolution rate of Quetiapine Fumarate than that of pure drug. The Solid dispersion with PVP K30 (1:5) by Solvent evaporation method showed faster dissolution rate as compared to other Solid dispersions. It is concluded that dissolution of the Quetiapine Fumarate could be improved by the Solid dispersion.