105DESIGN, OPTIMIZATION AND EVALUATION OF VEE GUM BASED RANITIDINE FLOATING GRANULES USING D-OPTIMAL DESIGN FOR OPTIMIZATION.Ranitidine is histamine H2 antagonist widely used in the treatment of gastric ulcer. It is suitable drug for gastro-retentive floating granules due to its short half life and poor absorption in lower gastro intestinal tract. In the present research work, D-optimal design was used for optimization of levels of independent variables (sodium bicarbonate, beeswax, ethyl cellulose and citric acid) on dependent variables 50 and time taken for 100% release in the formulations of ranitidine gastro-retentive floating granules with less experimentation. From the results it was concluded that sodium bicarbonate (10%), beeswax (20%) and ethyl cellulose (10%) and citric acid (0%) were favorable for formulation of gastro-retentive floating granules employing vee gum as release retardant.manjulamahesh58@gmail.comResearch712017Floating Granules,Floating Drug Delivery System,Controlled Release,Natural and Semi-Synthetic Polymers,D-Optimal DesignManjula Chella,R. Santosh KumarSrinivasa Rao College of Pharmacy, P.M. Palem, Visakhapatnam, Andhra Pradesh 530041, India,Srinivasa Rao College of Pharmacy, P.M. Palem, Visakhapatnam, Andhra Pradesh 530041, India