Simultaneous enantioseparation of three commonly used chiral antifungal pesticides (diniconazole, hexaconazole, and imazalil) was first studied based on micellar electrokinetic chromatography (MEKC) with hydroxypropyl-γ-CD (HP-γ-CD) as chiral selector. In this study, the importance of experimental parameters such as chiral selector type and concentration, sodium dodecyl sulfate (SDS) concentration, the ratio of methanol, and separation voltage in optimizing were investigated. The simultaneous enantioseparation of diniconazole, hexaconazole, and imazalil was successfully achieved in 30 mM borate buffer (pH 9.0) containing 10 mM HP-γ-CD and 20 mM SDS with methanol (8%) added as organic modifiers. The resolution of diniconazole, hexaconazole, and imazalil was 15.2, 2.12, and 2.78, respectively, and the peak efficiency (N) was over 566,825 plates/m. This study provides an alternative way to systematically separate chiral antifungal pesticides with high efficiency.
A new micellar electrokinetic capillary chromatography (MEKC) method combined with field-amplified sample injection (FASI) has been developed for the analysis of isonicotinamide and nicotinamide in whitening cosmetics and supplemented foodstuffs. Parameters affecting FASI preconcentration and MEKC separation were optimized systematically. Compared with direct MEKC, the sensitivity of FASI-MEKC was improved by 12.8- and 9.8-fold for isonicotinamide and nicotinamide, respectively. The detection limits (LODs) of isonicotinamide and nicotinamide were 0.051 μg mL−1 and 0.069 μg mL−1, respectively, with RSD (intraday) < 4.9% (n = 7, c = 0.5 μg mL−1) and RSD (interday) < 6.4% (n = 5, c = 0.5 μg mL−1). The proposed method was successfully applied in determination of isonicotinamide and nicotinamide in whitening cosmetics and supplemented foodstuffs with acceptable recoveries of 84.7–108.4%.
危险品化学品经营许可证（带存储）