Design and Evaluation of Sustained Release Matrix Tablets of Ibuprofen

The aim of the present work was to develop sustain release matrix formulation of ibuprofen and investigate the effects of both hydrophilic and hydrophobic polymers on in-vitro drug release. Ibuprofen is a non inflammatory agent used in symptomatic treatment of rheumatoid arthritis, osteoarthritis and ankylosing spondylitis and its biological half life is 4 hrs. Matrix tablets were prepared by wet granulation method using different concentration of Hydroxypropylmethylcellulose (HPMC K4M) and Ethyl Cellulose (EC) in alone and combination. The granules were evaluated for angle of repose, bulk density, tapped density, compressibility index and Hausners ratio. Prepared formulations were subjected to various studies like hardness, friability, thickness, % drug content, weight variation. In vitro release studies were performed using USP (XXI) six stage dissolution rate test apparatus I at 100 rpm in phosphate buffer (pH 6.8). The release kinetics was analysed using Zero-order model equation, Higuchi's square ischolar_main equation and Korsemeyer and Peppa's empirical equation indicated that diffusion along with erosion could be the mechanism of drug release. It was observed that combination of both the polymers exhibited the best release profile and able to sustain the drug release for prolong period of time. The %Cumulative drug Release graph shown below of Different formulations (F1-F9) with different polymer Concentration ratio. Release of the drug was retarded with increase in polymer concentrations. The optimized formulations were subjected to stability studies for three months at 40±2°C with RH 75±5%, and showed stability with respect to physicochemical parameters and release pattern. Multiple comparison analysis was confirmed that there exists a significant difference in the measured Higuchi release profile. So the combination of both hydrophilic and hydrophobic polymers successfully employed for formulating the sustained release matrix tablets of ibuprofen.