PREPARATION AND IN VITRO EVALUATION OF FELODIPINE-LOADED POLY(ε-CAPROLACTONE) MICROSPHERES: QUALITY BY DESIGN APPROACH

Felodipine was encapsulated into poly(epsilon-caprolactone) microspheres by the emulsion solvent evaporation method by employing the Quality by Design (QbD) strategy. Based on a risk analysis, the influence of 4 critical process parameters (type of stirrer, stirring rate, shape of mixing vessel, aqueous phase volume) on the critical quality attributes of the microspheres (size, polydispersity, entrapment efficiency (EE)), was evaluated by a full factorial experimental design. The microspheres' morphology and felodipine in vitro release were also studied. The particles' size ranged between 39.8 and 302.5 mu m, and the polydispersity index varied from 0.279 to 0.517. Felodipine EE was above 93.59%. Scanning electron microscopy (SEM) analysis revealed spherical particles, with imperfections and micropores on the surface. The microspheres exhibited an extended release of felodipine over a period of 12 hours. In conclusion, the QbD approach helped understand the process parameters and their impact on the quality profile in the development of felodipine-loaded microspheres.