Physicochemical characterization and in-vitro evaluation of flubiprofen oral controlled release matrix tablets: Role of ether derivative polymer ethocel

The main aim of the study was to develop once-daily controlled release matrix tablet of the selected propionic acid derivative flubiprofen (100 mg) using ethyl cellulose ether derivative release controlling polymer. Preformulation factors, including solubility, powder flowability and compressibility, and loss on drying were studied. Hausner's factor and angle of repose ranged from 1.10 to 1.25 and 25 to 29 respectively, indicating the best flowability and compressibility of the powder. Drug-polymer interaction was analyzed by particle size analysis, SEM and FTIR spectroscopy. Matrices were prepared by direct compression, with and without polymer. Effect of co-excipients like HPMC, starch and CMC, was studied on release behavior of the drug. The tablets were subjected to different physicochemical tests including hardness, friability, weight variation, % drug content, thickness and diameter with limits ranging from 6.4 +/- 0.24 to 6.9 +/- 0.44 kg/cm(2), 0.22 +/- 0.06 to 0.77 +/- 0.03 w/w, 200 +/- 1.3 to 203 +/- 1.0 g, 98.30 +/- 0.16 to 99.70 +/- 0.64%, 2.1 +/- 0.032 to 2.3 +/- 0.020 mm and 4.2 +/- 0.001 to 4.4 +/- 0.001 mm respectively. In-vitro drug release study was conducted in phosphate buffer ( pH 7.4) and different kinetic parameters were applied. Ethocel FP polymer alone showed the best anomalous release with exponent n = 0.793 with the linearity r(2) = 0.992, whereas the market brand released 90% of the drug after four hours with release exponent n = 0.210.