Development and characterization of pectin prednisolone microspheres for colon targeting

Abstract: The purpose of the present study was to obtain a novel microparticulate formulation of prednisolone, which was adequate for the treatment of ulcerative colitis.The formulations prepared were evaluated in vitro. Two types of pectin microspheres containing prednisolone named, pectin-prednisolone microspheres (PPMS)and pectin prednisolone eudragit microspheres (PPEMS), were prepared by an emulsion-dehydration technique and o/o solvent evaporation method respectively with some modifications. Various process variables as stirring speed, stirring time, as well as formulation variables i.e. polymer concentration and emulsifier concentration were optimized to get small uniform and spherical discrete microspheres. In vitro drug release studies were performed in presence of simulated gastric fluid, simulated gastric and intestinal fluid, and simulated intestinal fluid respectively, in presence or absence of rat caecal content. By coating the microspheres with eudragit S100 pH dependent release profiles were obtained The cumulative percent drug release of prednisolone from pectin microspheres in SGF and SIF after 4 hrs were varied from 30- 45 % and from eudragit coated microspheres after 4 hrs it varied from 6.25 to 8.95 % respectively. Further, the release of drug was observed higher in the presence of rat caecal contents, indicating the susceptibility of pectin to colonic enzymes released from rat caecal content. Key words: colon targeted drug delivery, prednisolone, ulcerative colitis In the controlled release area, biodegradabl