Floating In Situ Gel based on Alginate as Carrier for Stomach-Specific Drug Delivery of Famotidine

Alginate based floating in situ gelling systems of famotidine (FIGF) were prepared by dissolving varying concentrations of alginate in deionized water containing sodium citrate, to which varying concentrations of drug and calcium chloride was added and dissolved by stirring. Results of preliminary trials indicate that concentrations of sodium alginate, calcium chloride and sodium citrate affected the characteristics of in situ gel. A 3 full factorial design was employed to study the effect of independent variables, concentration of sodium alginate (X1) and concentration of calcium chloride (X2) on dependent variables, i.e. viscosity, drug content, drug release at 4 hrs (Q50) and drug release at 8 hrs (Q80). A sustained drug release was obtained for more than 8 hrs. In vivo testing of FIGF to albino Wistar rats demonstrated significant antiulcer effect of famotidine.