Formulation of gastroretentive sustained release floating in situ gelling drug delivery system of solubility enhanced curcumin-soy lecithin complex

摘要

Novel dry suspension based on floatingin situgelling systems of curcumin was formulated to assist in locally treating gastric ulcers. Curcumin is sparingly soluble in both water and lipophilic compounds and is very poorly absorbed in the small intestine where a pH of 7–8 makes it unstable. Solubility enhancement studies for curcumin were carried out considering three approaches (i) solid dispersion by fusion method (ii) solid dispersion by solvent evaporation method and (iii) complexation with soy-lecithin. The soy lecithin complexation method was found to improve the solubility of curcumin from 0.05?μg/ml to 130.9?μg/ml in pH 1.2 buffer. Thein vitrorelease studies of curcumin: soy lecithin (1:4) complex showed a statistically significant difference (p?=?0.0049) in release profile compared to that of curcumin alone. This complex was further incorporated in a gelling system containing gellan gum, calcium carbonate and sodium citrate which formed the basis of a floatingin situgelling system. The reconstituted dry suspension was evaluated for physical characteristics like viscosity, floating lag time, gel residence time and sedimentation volume. The system extended the release of curcumin in pH 1.2 buffer up to 12?h with anf2value 36.24 indicating a significant difference as compared to pure drug powder.