No abstract

The present work aims at fabricating the colon specific drug delivery of mesalamine (MES) by modified pulsincap technique and using natural polysaccharides. Mesalamine being poorly water soluble drug, solubility has been increased by solid dispersion technique using natural polymers such as guar gum (GG), hupu gum (HG) and xanthan gum (XG). Solid dispersions were prepared by kneading method at 1:1, 1:2 and 1:3 weight ratios (drug:polymer). The solid dispersions were characterized by FTIR, DSC studies and evaluated for practical yield, drug content. Saturation solubility, pH dependent solubility, phase solubility studies and dissolution studies were carried out. The solubility of the formulated solid dispersions was high when compared to pure drug. The order of drug release from the solid dispersions prepared by different gums are as follows GG>HG>XG and different ratio exhibited release as 1:3>1:2>1:1. The optimized solid dispersions have been exploited in the formulation of pulsincaps. Bodies were made insoluble by formaldehyde treatment. Solid dispersions of mesalamine were filled in the bodies. Guar gum (GG) was used as hydrogel plug. Sealing of body and cap was done using ethyl cellulose. Ethyl cellulose coating was employed on pulsincaps to ensure the capsule empties from the stomach intact. The pulsincaps were assessed for their dissolution profiles. Percent MES release from pulsincaps prepared with pure MES, MES-GG, MES-HG and MES-XG solid dispersions were found to be 63.22, 96.25, 94.90 and 93.05 respectively. Our studies have shown very effective and desirable mesalamine release profiles by pulsincap formulations at simulated colon pH condition, which can enable the drug delivery specifically at colon segment.