ABSTRACT:
Extended release press coated tablets of Mesalamine were designed with hydrophilic HPMC and enteric coated eudragit S-100 polymer. Combinations of hydrophilic polymers such as HPMC K4M, HPMC E5 and enteric coated eudragit S-100 polymers were used in different concentrations to formulate colon release tablets for giving the release of Mesalamine. Tablets of Mesalamine were prepared by direct compression using combined pH and time dependent approach and subjected to in vitro drug dissolution for 12h by using USP Type-II dissolution apparatus at speed of 100rpm at a temperature of 37 ± 0.5°C using simulated gastric fluid 900mL 0.1N HCl (pH 1.2) and Phosphate buffer pH 6.8 and 7.2. The combination of HPMC K4M: HPME E5 (70:30 %) with 8 % enteric coat of Eudragit S 100 were the optimum concentrations exerting lag time of 6 h. The PX-RD studies on optimized batch revealed amorphous nature. The DSC thermogram indicates no any interaction between drug and polymer. The absence of drug release during first 6 h is the lag period of 6 h that can be sufficient for delivery of Mesalamine in to the large intestine. Mesalamine press coated enteric coating tablet formulation may consecutively enhance the lag period and residence time of the drug in the colon and thus may potentiate its anti-inflammatory action.