Parmacokinetic evaluation of ibuprofen controlled release matrix tablets using hydrophilic Eudragit® polymer and co-excipients.

The present study was conducted to formulate controlled release dosage forms containing Ibuprofen with Eudragit® S 100 polymer. The tablets were formulated at three different ratios with the polymer to investigate the effect of different concentrations of polymer on in vitro drug release patterns/kinetics and in vivo absorption/pharmacokinetics. Pre-formulation studies were conducted including bulk density, tapped density, compressibility index, Hausner ratio and angle of repose. In vitro studies were conducted using phosphate buffer (pH 7.4) as dissolution medium. In vivo performance was evaluated using albino rabbits. Physico-chemical characteristics (i.e. dimensional tests, weight variation, hardness, friability and drug content determination) fell in the USP acceptable limits. The compressibility index was found to range between 12.02 ± 0.01% and 18.66 ± 0.03%, the Hausner ratio varied between 1.02 ± 0.01 and 1.19 ± 0.10 and the angle of repose ranged from 15.19 ± 0.01 to 24.52 ± 0.10, all indicating better flow properties than the bulk-reference standard. Both bulk and tapped densities also fell in the USP acceptable range. Ibuprofen market tablets showed Tmax of 2.1 ± 0.4h, which was significantly (P-value <0.05) lower compared to that of the reference standard (i.e. 4.09 ± 1.3h). Ibuprofen test formulation has a half-life (t1/2) of 16.9 ± 2.5h, which was significantly (P-value<0.001) higher compared to that of the reference standard (i.e. 9.23 ± 2.9h). Eudragit® S 100 polymers can be used efficiently to develop directly compressed prolonged release tablets.