QbD- a novel approach for design, optimization and evaluation of Linagliptin mucoadhesive microspheres

The quality by design (QbD) approach was applied for optimizing the formulation of model antidiabetic drug Linagliptin (LIN) mucoadhesive microspheres (MS) through design of experiment (DoE). To Optimize LIN-MS a quality target product profile (QTPP) was established in which critical quality attributes (CQAs) such as MVD, % encapsulation efficiency (% EE) and t50 drug release were quantified. As critical material attributes (CMA) viz., Keltone (KE), Carbopol (CA) and Pectin (PC) were chosen and evaluated their effect on CQAs. Response surface design (RSM) viz., Central Composite Design (CCD) was studied to evaluate effects of CMA on stated CQAs within the design space. The main effect was observed with varied levels of KE, CA and PC on CQAs. Numerical optimization by point prediction method was applied to generate optimized formula with predicted response, later the experimental responses were validated and ratified within the design space. The results suggest QbD through DoE appears to be a useful approach for the rational design, optimization and characterization of LIN-MS.