FORMULATION DEVELOPMENT STUDIES OF BILAYER TABLET GLIPIZIDE: A NOVEL AND EVOLUTIONARY APPROACH IN THE TREATMENT OF DIABETES.

Abstract Objective: The aim of present study is to formulate glipizide sustained release (SR) and immediate release (IR) bilayer matrix tablet by different concentration of Hydroxypropyl methylcellulose (HPMC) and Ethyl Cellulose (EC) to control the release pattern. Method: The sustained release layer of glipizide was prepared by using different grades of HPMC like, HPMC K-100, HPMC K-50 and Ethyl Cellulose along with other excipients by wet granulation technique. The immediate release layer of glipizide was prepared by Lactose and Sodium starch glycolate by wet granulation Method. Result: The powders were evaluated for their flow properties and the finished tablets were evaluated for their physical parameters. The both immediate release and sustained release layers of glipizide were characterized by FT-IR and in vitro dissolution studies. The drug release study of glipizide was evaluated using USP-II paddle type dissolution apparatus. The release rate of glipizide in immediate release layer was studied for 1h in pH 7.4 phosphate buffer media and that of glipizide in sustained release layer was studied for 10 h in pH 7.4 phosphate buffer media. Conclusion: From the six batches F3 batch showed good release behaviour 91.92percent of drug is released over 10 hours and r 2 value is 0.977 in zero-order kinetics. Glipizide is a poorly water soluble (BCS class 2) antidiabetic drug. Due to the poor water solubility of this drug, its bioavailability is dissolution rate-limited. Total four trial batches of each drug have been manufactured   to optimize and develop a robust and stable formulation, the stability studies of the products also comply with ICH guideline Keywords: Bilayer tablets, Glipizide, HPMC, Sustained release, Wet granulation.