RETRACTED CHAPTER: A Chiral Generic Strategy for Enantioseparation of Acidic and Basic Drugs Using Short End Injection Capillary Electrophoresis: Application to Design of Experiment

Abstract

The present work describes a capillary electrophoretic (CE) generic strategy used for chiral enantioseparation of Fluconazole (as an example of acidic drugs) and donepezil (as an example of basic drugs). Several modified cyclodextrins (CDs) were applied for enantioseparation of racemates such as highly sulfated α, γ CDs, hydroxyl propyl-β-CD, and sulfobutyl ether-β-CD. The starting screening conditions consist of 50 mM phosphate–triethanolamine buffer at pH 2.5, an applied voltage of 15 kV, and a temperature of 25 °C. The design of experiment (DOE) was based on a full factorial design of the crucial two factors (pH and %CD) at three levels, to make a total of nine (3²) experiments with high, intermediate, and low values for both factors. Evaluation of the proposed strategy pointed out that best resolution was obtained at pH 2.5 for the investigated racemates using low percentages of HS-γ-CD, while SBE-β-CD was the most successful chiral selector offering acceptable resolution, with best separation at low pH values and at higher %CD within 10 min runtime. Regression study showed that the linear model shows a significant lack of fit for all chiral selectors, anticipating that higher orders of the factors are most likely to be present in the equation with possible interactions.