Formulation And Dissolution Studies Of Solid Dispersions Of Nimesulide
Nimesulide, a highly water insoluble drug, exhibited poor dissolution pattern which perhaps is the reason for its poor absorption. Solid dispersions of nimesulide were prepared by fusion method using different carriers such as poloxamer PF-127, PEG 4000, citric acid, PVP, urea and mannitol. The ratio of drug: carrier chosen was 1:5 after initial trials with different ratios. They were evaluated for drug content, intactness of the drug in the formulations and dissolution. The drug content in the formulations varied from 76-84%. There was no interacton between the drug and the carriers as seen by their TLC. From the cumulative percent drug release data obtained by carrying out dissolution studies for a period of 3 h in 0.1 N HCl medium and the control study using 0.1% sodium lauryl sulphate, it was observed that the release rate constant of the formulations (0.289 to 561 h-1) were significantly greater than that of the drug (0.065 h-1) and the control (0.111 h-1). Poloxamer PF-127 was found to be the best carrier followed by PEG 4000 and urea.