Enantioseparation of Palonosetron Hydrochloride by Capillary Zone Electrophoresis with High-concentration β-CD as Chiral Selector

Abstract

The enantioseparation of four stereoisomers of palonosetron hydrochloride (PALO) by capillary zone electrophoresis using high concentration β-CD as chiral selector was described in this study. For optimization of the method of enantioseparation, several parameters such as β-CD concentration, separation buffer pH and concentration, the types and concentration of organic modifiers, and the applied voltage were evaluated. The optimum conditions were obtained as follows: 30 mmol L⁻¹ NaH₂PO₄ (pH 3.0) containing 150 mmol L⁻¹ β-CD and 10% (v/v) methanol with an applied voltage of 15 kV. Under these conditions, baseline separation of the four PALO stereoisomers was achieved within 35 min, and the reproducibility (expressed as relative standard deviation, RSD) of the migration times and the peak areas were below 0.5, 2.5% (intra-day), and 1.9, 4.4% (inter-day), respectively.