Formulation and in-vitro evaluation of floating microballoons of indomethacin

Objective of present study involves preparation and evaluation of floating microballoons of indometacin as a model drug, to increase its residence time in the stomach without contact with the mucosa. The microballoons were prepared by the emulsion solvent diffusion technique using different ratio of acrylic polymers (Eudragit RS100 and Eudragit S 100) as carriers. The yield of microballoons was up to 91.02 +/- 1.65%. Microballoons showed passable flow properties. On the basis of optical microscopy, particle size range was found to be ranging from 130.90 +/- 12.10 to 170.58 +/- 17.50 microm. Scanning electron microscopy (SEM) confirmed their spherical size, perforated smooth surface and a hollow cavity in them. Microballoons exhibited floating properties for more than 10 h. In vitro drug studies were performed in 0.1 M HCI with 0.1% SLS and phosphate buffer (pH 6.2). Different drug release kinetics models were applied for selected batches.