Application of Quality by Design for the Optimization of an HPLC Method to Determine Ezetimibe in a Supersaturable Self-Nanoemulsifying Formulation

Abstract

This paper describes the optimization of an isocratic stability indicating HPLC method for Ezetimibe (EZM). A five factor, three-level Box-Behnken experimental design optimized the method. The responses were (1) retention time, (2) tailing factor, and (3) theoretical plates. The quadratic effect of percentage (v/v) acetonitrile was the most significant (p < 0.001) factor to affect retention time and tailing factor, while interactions between percentage (v/v) acetonitrile and buffer pH had the most significant (p < 0.05) effect upon theoretical plates. The developed models for each response found to be well predictive bearing an acceptable adjusted correlation coefficient (0.9752 for retention time, 0.8557 for tailing factor, and 0.8336 for theoretical plates). The models were found to be significant (p < 0.001) having a high F value for each response (89.63 for retention time, 14.34 for tailing factor, and 12.27 for theoretical plates). The global desirability found to be 0.93 for the optimum chromatographic condition that achieved at a temperature of 35 ± 2°C using acetonitrile–potassium dihydrogen phosphate (pH 3.5; 20 mM) (45:55, v/v). The flow rate and injection volume kept at 0.8 mL min−1 and 20 µL, respectively. The optimized chromatographic method subsequently applied to quantify EZM from a novel supersaturable self-nanoemulsifying formulation.