Abstract:
The purpose of this study was to improve the dissolution and absorption rate of ibuprofen, a hydrophobic non-steroidal anti-inflammatory drug (NSAID), via polyethylene glycol 8000 (PEG 8000) solid dispersions. Ibuprofen-PEG 8000 solid dispersions (SDs) were prepared by fusion method using varying combination ratios of ibuprofen and polyethylene glycol (PEG) 8000 i.e. 1:1, 1:2, 1:3, and 1:4 (1 g :1 g, 1 g : 2 g, 1 g : 3 g, and 1 g : 4 g). Characterization based on surface morphology, particle size, absolute drug content, Fourier transform infrared (FT-IR) spectroscopy and micromeritic properties were carried out on the SDs. The in vivo release of ibuprofen from the SDs was performed using rats. Greenish brown, discrete, flowable and irregularly shaped SDs of mean particle size range 113.5 ± 2.5 to 252.5 ± 1.9 µm, which were stable over 3 months, were obtained. The higher the polymer (PEG 8000), the smaller the particle sizes of the SDs, which were less than the mean particle size of the physical mixture. The encapsulation efficiency (EE %) of the SDs ranged from 73.4 ± 2.9 % to 83.5 ± 2.7%. The encapsulation efficiency of the physical mixture (67.0 ± 1.8) was lower than those of the SDs. While the EE % increased with increased concentration of PEG 8000 in the SDs the mean particle size decreased with increased concentration. The FT-IR results indicate no strong chemical interaction of ibuprofen and PEG 8000 in the SDs. Administration of the SDs to rats resulted in much higher plasma concentration compared to the pure ibuprofen and the physical mixture (p<0.05), an indication of enhanced absorption rate of ibuprofen in the SDs systems. This study has shown that ibuprofen-PEG 8000 SDs could offer a better and more effective approach of increasing the dissolution and absorption rate of the drug.

Keywords: Ibuprofen, Solid Dispersion, PEG 8000, Plasma Concentration, Non-Steroidal Anti-inflammatory Drug (NSAID).