formulation and in-vitro characterization of extended release pellets of indomethacin using powder-layering technique

the most frequent adverse effects of indomethacin like other nsaids are gastro–intestinal and central nervous system disturbances. extended release or enteric release formulations minimize these symptoms. the objective of this study was to develop an extended release pellet formulation of indomethacin by the centrifugation (rotary fluid bed granulation) or powder layering method. layered, nonpareil pellets composed of sugar, avicel ph 101 and lactose were prepared using freund cf-granulator and were treated by a binder solution (hpc-l) applied by spray gun. a conical designed powder-feeding unit applied the drug powder. drug content of pellets was determined by hplc method. eudragit ne 30 d was used for coating the prepared pellets. the results show that increasing the amount of eudragit ne 30 d, opadray and sds in coating solution adjusts release of the pellets. the dissolution profile achieved from pellets containing 500 g nonpareil, 400 g indomethacin, 400 ml hpc 8%, 61g talc, 50 g opadray® and coating consisted of 37.5 g eudragit ne 30 d, 1.8 g sds, 7.5 g opadray® passed usp30 standards for indomethacin release and was comparable with retard indocid®75 capsule from mds company.