A quality by design assisted RP-HPLC method utilizing central composite design for the assay of eliglustat and its organic impurities in drug

This study aimed to develop a stability-indicating RP-HPLC assay method for eliglustat and its organic impurities using a central composite design approach. The chromatographic separation was achieved with a 10 mM phosphate buffer at pH 4.0 on a Thermo Accucore C18 column (150 x 4.6 mm, 2.6 mu m) at a wavelength of 210 nm. Gradient elution was performed using a mobile phase-A consisting of buffer and acetonitrile in a 90:10 v/v ratio and a mobile phase-B composed of water and acetonitrile in a 35:65 v/v ratio, at a flow rate of 1.1 mL/min at 45 degrees C for a total run time of 55 minutes. Based on preliminary experiments, central composite design was utilized to evaluate the effects of independent variables such as flow rate, acetonitrile ratio and column oven temperature on the response factors. Eliglustat and its impurities (EGS-5A, EGS-Diastereomers, and EGS-N-Oxide) had retention time of 3.5 minutes, 21.5 minutes, 23.2 minutes and 25.9 minutes, respectively. The limits of detection and quantitation for eliglustat and its impurities were established in relation to the test concentration, achieving a desirability of 1. The developed method was validated as per regulatory guidelines and successfully applied in bulk drugs and formulation.