Department of College of Ecology and Resource Engineering, Wuyi University, China.
Department of Chemistry, National Kaohsiung Normal University, Taiwan.
J Food Drug Anal. 2018 Jul;26(3):1171-1179. doi: 10.1016/j.jfda.2017.12.002. Epub 2018 Jan 12.
This study developed a sensitive method involving capillary electrophoresis (CE) coupled with ultraviolet absorption for the simultaneous separation of chiral phenothiazine drugs at nanomolar concentration levels. The method consists of hydroxypropyl-γ-cyclodextrin (Hp-γ-CD) as a chiral selector and poly (diallyldimethylammonium chloride) (PDDAC)-based CE. Five pairs of d,l-phenothiazines were baseline separated using a background electrolyte containing 0.9% PDDAC, 5 mM Hp-γ-CD, and 100 mM tris(hydroxymethyl)aminomethane (Tris)-formate (pH 3.0). The five pairs were successfully stacked on the basis of the difference in viscosity between the PDDAC-containing background electrolyte and the sample solution, with almost no loss of resolution. The combination of a solid-phase extraction and PDDAC-mediated CE can efficiently improve the sensitivity of the phenothiazine enantiomers. Under optimal conditions, calibration graphs displayed the linear range between 6 and 1500 nM, with relative standard deviation values lower than 3.5% (n = 5). Detection limit ranged from 2.1 to 6.3 nM for target analytes, and 607- to 1555-fold enhancement was achieved. The practicality of using the proposed method to determine five pairs of d,l-phenothiazines in urine is also validated, in which recoveries between recoveries of all phenothiazines from urine ranged from 89% to 101%.
本研究开发了一种灵敏的方法，涉及毛细管电泳（CE）与紫外吸收相结合，可在纳摩尔浓度水平下同时分离手性吩噻嗪类药物。该方法由羟丙基-γ-环糊精（Hp-γ-CD）作为手性选择体和基于聚二烯丙基二甲基氯化铵（PDDAC）的 CE 组成。使用含有 0.9% PDDAC、5 mM Hp-γ-CD 和 100 mM 三羟甲基氨基甲烷（Tris）-甲酸（pH 3.0）的背景电解质，可将 5 对 d,l-吩噻嗪基线分离。基于含 PDDAC 的背景电解质和样品溶液之间的粘度差异，可成功地将这 5 对化合物进行堆积，几乎不会损失分辨率。固相萃取和 PDDAC 介导的 CE 的结合可有效提高吩噻嗪对映体的灵敏度。在最佳条件下，校准曲线在 6 至 1500 nM 之间呈线性，相对标准偏差值低于 3.5%（n = 5）。检测限为目标分析物的 2.1 至 6.3 nM，实现了 607 至 1555 倍的增强。还验证了该方法在尿液中测定 5 对 d,l-吩噻嗪的实用性，所有从尿液中提取的吩噻嗪的回收率在 89%至 101%之间。
