Enantioseparation of ketoconazole and miconazole by capillary electrophoresis and a study on their inclusion interactions with β-cyclodextrin and derivatives

A chiral separation method coupled with capillary electrophoresis (CE) analysis for ketoconazole and miconazole enantiomers using chiral selectors such as beta-cyclodextrin (beta-CD) and hydroxypropyl-beta-CD (HP-beta-CD) was developed in this study, which included the optimisation, validation and application of the method on the antifungal cream samples. The formation of inclusion complex between the hosts (beta-CD and HP-beta-CD) and guests (ketoconazole and miconazole) were compared and analysed using ultraviolet-visible spectrophotometry, nuclear magnetic resonance (NMR) spectroscopy and molecular docking methods. Results from the study showed that in a concentration that ranged between 0.25 and 50 mg L-1, the linear calibration curves of each enantiomer had a high coefficient of regression (R-2 > 0.999), low limit of detection (0.075 mg L-1) and low limit of quantification (0.25 mg L-1). The relative standard deviation (RSD) of the intraday and interday analyses ranged from 0.79% to 8.01% and 3.30% to 11.43%, respectively, while the recoveries ranged from 82.0% to 105.7% (RSD < 7%, n = 3). The most probable structure of the inclusion complexes was proposed based on the findings from the molecular docking studies conducted using the PatchDock server.