Preparation and Evaluation of Etodolac Loaded Eudragit Rs 100 Microcapsules using Quality by Design Approach

The objective of the current study was to design and optimize Etodolac loaded Eudragit RS 100 microcapsules using solvent evaporation method. Quality by design approach was implemented for development of Etodolac microcapsules using I-Optimal RSM design. Based on initial risk assessment and preliminary study, two independent variables, Drug: Eudragit RS 100 ratio and stirring speed were selected for Design of Experimentation (DoE) to see effect on critical quality attributes (CQAs); entrapment efficiency and particle size. The prepared Etodolac loaded Eudragit RS 100 microcapsules were characterized for particle size, entrapment efficiency, in-vitro dissolution study, DSC, XRD and SEM. Acceptance criteria for CQAs were considered as particle size in the range of 22-200 µm and entrapment efficiency in the range of 72.86-97.25 %, which generated the design space with combination of selected critical parameters leading to the acceptable operating ranges for formulating microcapsules with respect to desired Target Quality Product Profile (TQPP). The obtained Etodolac loaded Eudragit RS 100 microcapsules were spherical in shape, having better entrapment efficiency and sustained drug release profile. Validation of model was carried out by comparing experimental values with predicted value of optimized formulation. Optimized formulations within design space were capable of sustaining drug release for about 22 hours and were expected to reduce dosing frequency thus reducing side effects associated with therapy.