Quality by Design (QbD) Approach to Develop HPLC Method for Estimation of Gliclazide and its Impurity (Gliclazide Impurity A) in Bulk Drug

Background: Gliclazide Impurity A (GI-A) is one of the gliclazide impurities, as described in the European Pharmacopoeia. Objective: The objective of this study was to develop and validate simple, robust and accurate Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) method for estimation of gliclazide along with GI-A in bulk by optimising chromatographic parameters using Box Behnken design in response surface methodology. Methods & Results: Box Behnken design was employed for optimizing flow rate, injection volume and strength of the buffer in order to minimize retention time of both gliclazide and GI-A. The optimized strength of orthophosphoric acid buffer in a mixture of Acetonitrile (50:50 v/v), flow rate and injection volume were found to be 25mM, 1mL/min, 20 mu L respectively. Linearity was observed in concentration range of 25-150 mu g/mL (r(2) =0.999). The retention time of gliclazide and GI-A was found to be 5.799 minutes and 3.819 minutes, respectively. The limit of detection for Gliclazide and GI-A was found to be 0.0066, and 0.0075 mu g/mL and the limit of quantification limit was found to be 0.0202, 0.0228 mu g/mL, respectively. The developed method was validated as per the ICH guidelines. Conclusion: The proposed method is useful for best analysis of Gliclazide and GI-A in pharmaceutical dosage forms. QbD approach was found to be an effective tool for optimising chromatographic conditions of the proposed method.