Abstract
In the present investigation, an attempt was made to formulate the time and pH dependent drug delivery system, reduce the frequency of dose administeration, and prevent ulcerative colitis by developing sustained delayed release tablets using a combination of Eudragit S-100 and L-100 as enteric coating. The core tablets of Celecoxib were prepared using the direct compresion method. The aim of the present study is to develop colon specific drug delivery of Celecoxib sustained release enteric coated tablet for ulcerative colitis using HPMC K-4M as a semisynthetic polymer. The impact of polymer concentration and superdisintegrant concentration was also studied. In-vitro drug release research was performed on the enteric coated Celecoxib tablet using simulated gastric fluid (0.1N HCl) for 2 hours, simulated intestinal fluid (pH 7.4) for 3 hours, and the simulated colonic fluid (pH 6.8) for 7 hours as a dissolution fluid. The study showed that the coating had a significant impact on the lag time before medication release. In the treatment of colonic illness and the oral administration of medications that are unstable and vulnerable to enzymatic degradation in the upper GI tract, colon drug delivery is advantageous. The results also showed that a mixture of Eudragit S-100 and L-100 may be used to coat tablets for medication delivery to the colon

Key words: Colon drug delivery system , Targeted System, Enteric coated tablet , Time and pH dependent system.