Formulation and evaluation of floating in situ gel of Nizatidine

Abstract

The present investigation concerns with the development and optimization of an floating in-situ gelling formulation of Nizatidine. It is H2-receptor antagonist absorbed from the upper gastrointestinal tract and it is preferentially localized in parietal cells of gastric mucosa. The polymer used in the study is Sodium alginate which forms a gel when it comes in contact with simulated gastric fluid. The principle of gelling involves supply of complexed calcium ions in form of calcium carbonate that are released in the acidic environment of the stomach. The formulations are designed by using 3² full factorial design. Sodium alginate sols of various concentrations were prepared by dissolving variable amount of sodium alginate in deionized water. In sodium alginate solution variable amounts of calcium carbonate were added so as to obtain nine different formulations. The amount of Nizatidine is kept constant for all nine formulations. The F5 formulation showed optimum drug release. The gels were evaluated with respect to In Vitro Drug Release Appearance of gel, Viscosity of In Situ Gelling Solution, in vitro Floating Study, Content uniformity and pH Measurement. Stability study was done according to ICH guidelines. This study reports that the aqueous solutions of nizatidine containing sodium alginate forms in situ gel in acidic environment. The results of a 3² full factorial design revealed that the concentration of sodium alginate and concentration of calcium carbonate significantly affected on the dependent variables like viscosity, floating lag time, drug release The in- vivo study shows significant anti-ulcer effect of alginate based in situ gel of nizatidine.