QbD - A novel approach for design, optimization and evaluation of sitagliptin mucoadhesive microspheres

Quality by Design (QbD) represents a highly systematic approach implementing the Design of Experiment (DoE) for finding the optimal product and process characteristics. Sitagliptin (SIT), a potent and selective dipeptidyl peptidase (DPP) IV inhibitor. Typically, it improves the glycaemic control by increasing the active level of incretin peptides particularly glucagon like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide. A response surface CCD studied by using Design Expert Stat-Ease software. The study includes two factors (independent variable) viz., Sodium alginate (SA) (X1), Carbopol (CA) (X2 ), 2 levels (-1, +1), three response (dependent variables) viz., Particle size (Y1), % EE (Y2), t50 (Y3), 13 runs with 5 center point. The design trials of SIT loaded mucoadhesive microspheres (SIT-MS) were fabricated by ionotropic gelation method. The SIT-MS were characterized for design response and further CCD was applied for studying the influence of factors on response. The optimized formulas generated as per CCD was formulated, characterized and validated with predicted values. FTIR studies showed no interaction between drug and polymers. ANOVA suggest that few model terms are significant (p < 0.05) suggest significant first order linear and quadratic model. The R2 values suggest significant correlation between the factors and response. The quadratic polynomial equations suggest linear and quadratic terms influence on stated response and justified by 2D contour, 3D surface plot. The experimental values of optimized formulations ratified with predicted values. The QbD through CCD results concludes that DoE can be carried out successfully for formulation, characterization and optimization of SIT-MS.