Mucoadhesive microparticulate drug delivery system of curcumin against Helicobacter pylori infection: Design, development and optimization

The purpose of the present research was to develop and characterize mucoadhesive microspheres of curcumin for the potential use of treating gastric adenocarcinoma, gastric and duodenal ulcer associated with Helicobacter pylori. Curcumin mucoadhesive microspheres were prepared using ethyl cellulose as a matrix and carbopol 934P as a mucoadhesive polymer by an emulsion-solvent evaporation technique. Response surface methodology was used for optimization of formulation using central composite design (CCD) for two factors at three levels each was employed to study the effect of independent variables, drug:polymer:polymer ratio (curcumin:ethylcellulose:carbopol 934P)(X-1) and surfactant concentration (X-2) on dependent variables, namely drug entrapment efficiency (DEE), percentage mucoadhesion (PM), in vitro drug release and particle size (PS). Optimized formulation was obtained using desirability approach of numerical optimization. The experimental values of DEE, PM, % release and PS after 8 h for the optimized formulation were found to be 50.256 +/- 1.38%, 66.23% +/- 0.06, 73.564 +/- 1.32%, and 139.881 +/- 2.56 mu m, respectively, which were in close agreement with those predicted by the mathematical models. The drug release was also found to be slow and extended more than 8 h and release rates were fitted to the Power law equation and Higuchi model to compute the diffusional parameters. The prolonged stomach residence time of curcumin mucoadhesive microspheres might make a contribution to H. pylori complete eradication in combination with other antimicrobial agents.