Development and Characterization of Repaglinide Loaded Floating Microparticles

Abstract

Sustained release drug delivery has been successfully achieved using microparticles made from natural or synthetic polymers. The aim of this study is to develop and test floating microparticles of Repaglinide in order to improve drug bioavailability by extending gastric residence time. Repaglinide, an oral hypoglycemic, is a lipophilic drug that is rapidly absorbed from the stomach and eliminated with a half-life of just 1 h, so suitable to be formulated as floating drug delivery system for sustained release.Repaglinide floating microparticles were developed using an ionotropic gelation method that included calcium chloride as a cross-linking agent, sodium alginate, and different concentrations of hydroxypropyl methylcellulose (HPMC), ethyl cellulose (EC), and sodium bicarbonate (NaHCO3). A three factor, three-level Box-Behnken design was used to study the effect of independent variables on dependent variables. In the formulation of microparticles, the amount of hydroxypropyl methylcellulose (X1), ethyl cellulose (X2), and sodium bicarbonate (X3) were three independent variables, while percentage buoyancy (Y1) and percentage drug release at 10 h (Y2) were dependent variables. Micromeritic properties, percent yield, percent drug entrapment performance, surface morphology, percent buoyancy, in-vitro drug release, and drug excipient compatibility were all assessed in the formulations.FTIR studies revealed no interaction between the drug and the excipients.SEM for surface morphology studies revealed that their surface is spherical and smooth. The mean particle size of formulations was found to be between 415- 689 µm, the drug entrapment efficiency was found to be between 44.65% - 76.55% and percent buoyancy was noted to be between 63%- 78.33%. The results revealed that entrapment efficiency increased as polymer concentration was increased. The cumulative percent drug release after 10 h was noted to be between 76.87- 88.12%. Percent drug release decreased as polymers concentration was increased. The buoyancy was increased with increasing concentration of sodium bicarbonate. The developed microparticles could successfully retard the release of the drug.