FORMULATION AND IN VITRO EVALUATION OF AMLODIPINE GASTRORETENTIVE FLOATING TABLETS USING A COMBINATION OF HYDROPHILIC AND HYDROPHOBIC POLYMERS

Objective: The aim of this study was to formulate a developed floating tablet of amlodipine using different concentrations and types of hydrophilic and hydrophobic polymers to be conserved in the stomach for modulating solubility and bioavailability, diminishes drug waste and decline side effects.Methods: Through this study, eleven innovative formulations of amlodipine floating tablets were prepared [mixture of amlodipine, sodium bicarbonate (NaHCO3), hydroxypropyl methylcellulose (HPMC) E50, HPMC K100M, ethylcellulose (EC) 5 mp. a. s.] by direct compression method. The pre-compressed mixtures were then evaluated for numerous parameters such as angle of repose, bulk density, tapped density, Carr's compressibility index and Hausner's ratio. After compression, tablets were subjected to several tests like; floating behavior of tablets, tablet thickness, hardness test, friability test, weight variation, in vitro dissolution test. In addition, the optimum formulation was evaluated for Fourier transform-infrared (FT-IR) and differential scanning calorimetry (DSC) tests. Results: From in vitro dissolution tests and kinetic assessments; F8 was selected as an optimum formula, depending on the R2 value of zero order kinetics (0.9915) and (n) value of Korsmeyer-Peppas (0.9635) which indicate purely relaxation zero order kinetic with good delaying in drug release that was reached to 14 h.Conclusion: It can be concluded that the developed formulation of a certain combination of low viscosity grades of HPMC and EC was considered an efficient floating tablet.