FORMULATION AND CHARACTERIZATION OF GASTRORETENTIVE FLOATING MICROSPHERES OF METOPROLOL SUCCINATE

Abstract

Gastro-retentive drug delivery systems have gained considerable attention as a promising approach for prolonging gastric residence time and achieving sustained drug release. In the present study, floating microspheres of Metoprolol succinate were developed to provide controlled drug delivery and prolonged gastric retention. The microspheres were prepared by the emulsion solvent evaporation method using ethyl cellulose and Eudragit RS 100 as release-retarding polymers, calcium silicate as a buoyancy-enhancing agent, PVA as a stabilizer, and ethanol: dichloromethane (1:2) as the solvent system. Eight formulations (F1–F8) were prepared with varying polymer concentrations and evaluated for micromeritic properties, particle size, percentage yield, drug content, drug entrapment efficiency, surface morphology, floating behavior, and in-vitro drug release. The prepared microspheres showed satisfactory characteristics, with particle size ranging from 50–82 µm, percentage yield of 72–88%, drug content of 90.18–96.43%, floating duration of 7–14 h, floating lag time of 1.05–3.03 min, and drug entrapment efficiency of 72–92%. In-vitro drug-release studies demonstrated sustained drug release over 12 h, with cumulative drug release ranging from 82.80–92.15%. Among the formulations, F3 was selected as the optimized formulation, exhibiting 81% yield, 75 µm particle size, 96.43% drug content, 86% drug entrapment efficiency, 14 h floating duration, and 85.40% drug release at 12 h. Overall, the study demonstrated the successful development of floating microspheres with prolonged buoyancy and controlled drug release, and formulation F3 showed the most desirable combination of pharmaceutical characteristics, indicating its potential as a gastro-retentive system for sustained delivery of Metoprolol succinate.