FORMULATION AND EVALUATION OF IBUPROFEN LOADED AGAR MICROBEADS

Ibuprofen embedded agar microbeads were prepared by two stage process involving extrusion and dispersed phase congealing technique. Five formulations were prepared and the amount of agar was constant in each formulation. The amount of sodium carboxymethyl cellulose (SCMC) was 0%, 0.5%, 1%, 1.5% and 2% in the formulation F-1, F-2, F-3, F-4 and F-5 respectively. The prepared microbeads were evaluated for %yield, size, drug content and drug release. The size of the beads was found in the range of 1.52±0.00-1.86±0.43 mm. The size of the microbeads increased with increase in the concentration of the SCMC present in the polymer blend. The results showed that the yield of microbeads collected after drying was 79.34±0.019 -89.59±0.012% w/w and the drug content was found in the range of 59.54±1.23-78.46±1.78%. Release of ibuprofen from the agar microbeads was studied in phosphate buffer (pH 7.5) solution for 5 h in USP (Type-I) basket type dissolution test apparatus at 37±1°C. It was observed that F-2, F-3, F-4 and F-5 were best fitted with zero order model indicating their continuous and controlled release kinetics. Again the release kinetics of F-2, F-3, F-4 and F-5 were found to be governed by Higuchi model that indicated their release mainly occurred by diffusion followed by pore formation. From the in vitro release data it was observed that the rate of drug release from the microbeads could be controlled by increasing the concentration of the added hydrocolloid (SCMC).