هاي با وزن مولكولي مختلف PEG افزايش سرعت انحلال ايندومتاسين در پراكندگيهاي جامد تهيه شده با

Dissolution Enhancement of indomethacin by solid dispersions prepared with polyethylene glycoles of different molecular weights

OBJECTIVES: This study was designed to increase the dissolution rate of poorly water soluble anti rheumatic agent, indomethacin, preparing solid dispersion with different with polyethylene glycoles of different molecular weights, and to study the mechanism of enhanced dissolution properties. Methods: PEG 2000, PEG, PEGiooo and PEGS were used as carriers and the solid dispersions were prepared by modified solvent method. Evaluation of solid dispersion properties was performed using solubility measurements, dissolution studies. Fourier-transform infrared spectroscopy and X-ray powder diffractometery (PXRD). Results: The results from solubility measurement indicated that, the solubility of indomethacin increased as the concentration and the molecular weight of PEG incased. The dissolution data revealed that these carriers can enhance the in vitro dissolution rate of indomethacin in both SGF (Simulated Gastric Fluid) and SIF (Simulated Intestinal Fluid) media. The results of infrared spectroscopy together with those from x-ray diffraction showed no drug-carrier interactions and indomethacin was still detectable in its solid state in all solid dispersions. Conclusion: An increased dissolution rate of indomethacin at pH 12 and 7.2 was observed when the drug was dispersed in these carriers. The solubilization effect of polyethylene glycoles as well as the reduction of particle aggregation and an alteration of the surface properties of the drug particles might be responsible for the enhanced dissolution rate.