Development of Colon-targeted Microsponges for the Treatment of Inflammatory Bowel Disease

The present study is aimed to develop and characterize microsponge-based novel colon-specific drug delivery systems containing 5-amino salicylic acid for the treatment of inflammatory bowel disease. Initially, microsponges of 5-amino salicylic acid were prepared by quasi-emulsion solvent diffusion method using Eudragit RS100, Eudragit S-100 and Eudragit L100. Different formulations of microsponges using three acid resistant polymers, Eudragit S100, Eudragit L100, Eudragit RS100 in drug:polymer ratios of 1:1, 1:0.5, 1:0.25 with each polymer were prepared and evaluated for physicochemical, morphological characteristics and in vitro parameters. Among these nine formulations, ES1, EL1 and ERS1 were selected, sieved and compressed into tablets, T-ES1, T-EL1, T-ERS1 and evaluated. Among the 3 batches of tablet formulations prepared, T-ES1 showed the best release rate for the drug, which followed zero order release kinetics with diffusion case II transport mechanism.