Studies On Suspension Of Nimesulide Solid Dispersion : Development, Characterization And In Vivo Evaluation
The present study aimed at enhancing solubility and dissolution of nimesulide by applying solid dispersion technique followed by formulating it as suspension. Solid dispersions of nimesulide were prepared using propylene glycol, polyvinyl pyrrolidine-K30 and polyethylene glycol-6000 and formulated as respective suspensions. The suspensions were characterized by studying the particle size and sedimentation volume (Hu/Ho). In vitro evaluation was carried out in USP XXI dissolution apparatus. The in vivo evaluation of nimesulide suspensions were carried out in carrageenan induced rat paw edema method. Long term stability studies were carried out at different temperatures. Nimesulide suspensions with solid dispersion exhibited good suspendability and gave higher dissolution rates than those with plain nimesulide suspension. They also demonstrated enhanced anti-inflammatory activity when compared with plain drug suspension. The percentage edema inhibition obtained for different suspensions of nimesulide solid dispersion F2, F3 and F4 after 1 h were 76%, 79% and 82%, respectively. On the other hand edema inhibition of plain nimesulide suspension was only 40%. It can be concluded from the study that the suspension of nimesulide solid dispersion exhibited improved dissolution profiles, stability and in vivo efficacy.