Utilizing central composite design (CCD) in the optimization of new HPLC-PDA method for the assay of daridorexant: Application to the analysis in bulk and tablet dosage forms

AbstractIn this study, we developed a robust Quality by Design guided reverse phase high-performance liquid chromatographic method for quantifying daridorexant with simplicity, speed, sensitivity, reproducibility, and cost-effectiveness. Utilizing a Waters e2690 alliance HPLC system with Empower 2® software control and a SpursilTM C18 HPLC column, critical method parameters such as flow rate, % aqueous buffer and buffer pH were identified through preliminary trials and risk assessment studies. Optimization via central composite design as part of a Design of Experiments framework, with retention time and tailing factor as critical analytical attributes, resulted in optimized chromatographic conditions: 30:70 (% v/v) phosphate buffer (pH 3) and acetonitrile as mobile phase, flowing at 1.0 mL/min, with detection at 270 nm. The method exhibited linearity within a range of 2.0-10.0 μg/ mL (correlation coefficient: 0.9997) and detection, quantitation limits of 0.089 μg/mL and 0.271 μg/mL, respectively. Validation according to ICH Q2 (R1) guidelines confirmed the method's robustness, precision, accuracy, sensitivity, and high linearity for daridorexant estimation in both bulk drug and marketed formulations.GRAPHICAL ABSTRACTDisplay full sizeKeywords: DaridorexantCentral composite designCritical method parametersCritical analytical attributes