Analytical Quality by Design Assisted HPLC Method for Quantification of Canagliflozin/ Metformin and Stability Studies

Aim: Current work entails the analytical quality by design (AQbD) based robust HPLC method for real-time analysis of canagliflozin and metformin. Different pKa values of two drugs made their chromatographic separation critical. Materials and Methods: The critical method parameters were systematically optimized using factorial experimental design (central composite design) and contours were generated as a function of significant variables when analyzed in the modeling software. The method operable design region that control the variation in response is obtained from contour plot and verified experimentally. Results: Effective chromatographic separation of title analytes was accomplished on SPOLAR C18 (250 x 4.6 mm, 5µ) column at 25°C with mobile phase comprising of phosphate buffer, pH 6.0 and acetonitrile (55:45 % v/v), pumped at a flow rate of 0.8 mL/ min by isocratic elution pattern and UV detection at 254 nm. The linear model was established in the range of 50–300 and 5-30 and µg/mL at retention times of 3.24 and 10.77 min for metformin and canagliflozin, respectively. Conclusion: Method obeyed all validation parameters of ICH Q2 (R1) guidelines and able to discriminate the Adduct generated upon drug degradation. The proposed method was pertinent for assay drugs and extended to quantify the drugs in prevalence of biological matrix.