Formulation and Evaluation of Colon Targeted Tablets of Mesalazine

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, to prevent ulcerative colitis by developing sustained delayed release tablets of Mesalazine using combination of Eudragit S-100 and L-100 as enteric coating. The core tablets of Mesalazine were prepared using wet granulation containing a superdisintegrant. The aim of present study is to develop colon specific drug delivery of Mesalazine sustained release matrix tablets for ulcerative colitis using HPMC K-4M and HPMC K-15M as a semisynthetic polymer. Effect of polymer concentration and superdisintegrant level was also investigated. The matrix tablets of Mesalazine are subjected to an in-vitro drug release study using simulated gastric fluid (0.1N HCl) for 2 hours, simulated intestinal fluid (pH 7.4) for 3 hours and simulated colonic fluid (pH 6.8) for 7 hours as dissolution fluid. The study showed that, lag time prior to drug release was highly affected by the coating. Colon drug delivery is advantageous in treatment of colonic disease and oral delivery of drugs that are unstable and susceptible to enzymatic degradation in upper GI tract. The disintegration data obtained from tablets demonstrated that disintegration data rate of studied tablets is dependent on: (i) The polymer used to coat the tablets (ii) pH of disintegration media. Results also demonstrated that combination of Eudragit S-100 and L-100 can be successfully used to coat tablets for colon targeted delivery of drug.