Department of Chemistry, National Kaohsiung Normal University, No.62 Shenjhong Rd., Yanchao District, Kaohsiung City, 82446, Taiwan.
Anal Bioanal Chem. 2020 Aug;412(21):5113-5123. doi: 10.1007/s00216-020-02441-x. Epub 2020 Mar 11.
A rapid, simple, and sensitive technique for the quantitative detection of fluoxetine and norfluoxetine enantiomers in biological fluids was developed based on the combination of field-amplified sample stacking (FASS)-related capillary electrophoresis (CE) with ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME). The extraction efficiency of UA-DLLME was strongly related to extraction time, salt concentration, type of extraction and dispersion solvents, and volume of extraction and dispersion solvents. The extracted fluoxetine and norfluoxetine enantiomers in a mixture of 50% methanol and 50% deionized water were efficiently stacked using FASS and then separated using cyclodextrin-modified CE. Under optimal conditions of FASS (chiral selector, 3 mM trimethyl-β-cyclodextrin; and background electrolyte, 100 mM phosphate buffer) and UA-DLLME (extraction solvent, 200 μL of acetone; and dispersed solvent, 50 μL of CHCl in 1 mL of the sample solution), the obtained enrichment factors of fluoxetine and norfluoxetine enantiomers reached approximately 2000. The linear ranges for the quantification of fluoxetine and norfluoxetine enantiomers were 0.3-150 and 0.6-150 nM, respectively. The relative standard deviations in peak areas and migration time for four analytes were less than 3.3% and 6.3%, respectively. The proposed system provided limits of detection (signal-to-noise ratio of 3) for four analytes corresponding to 0.1 nM. The precision and accuracy for urine and serum samples were less than 6.8 and 8.3%, respectively. These findings suggested that the proposed system exhibited a high potential for the reliable determination of fluoxetine and norfluoxetine enantiomers in clinical samples. Graphical abstract.
一种基于场放大样品堆积（FASS）相关毛细管电泳（CE）与超声辅助分散液-液微萃取（UA-DLLME）相结合的快速、简单、灵敏的检测生物流体中氟西汀和去甲氟西汀对映体的定量检测技术。UA-DLLME 的萃取效率与萃取时间、盐浓度、萃取和分散溶剂的类型以及萃取和分散溶剂的体积密切相关。在甲醇和去离子水各 50%的混合物中，氟西汀和去甲氟西汀对映体经 50%甲醇和 50%去离子水的混合物提取后，用 FASS 有效地堆积，然后用环糊精修饰的 CE 分离。在 FASS 的最佳条件下（手性选择器，3mM 三甲基-β-环糊精；背景电解质，100mM 磷酸盐缓冲液）和 UA-DLLME（萃取溶剂，200μL 丙酮；和分散溶剂，1mL 样品溶液中的 50μL CHCl ），氟西汀和去甲氟西汀对映体的富集因子达到约 2000。氟西汀和去甲氟西汀对映体的定量线性范围分别为 0.3-150 和 0.6-150nM。四种分析物的峰面积和迁移时间的相对标准偏差均小于 3.3%和 6.3%。该系统对四种分析物的检测限（信噪比为 3）分别对应 0.1nM。尿样和血清样品的精密度和准确度均小于 6.8%和 8.3%。这些发现表明，该系统在临床样品中氟西汀和去甲氟西汀对映体的可靠测定中具有很高的应用潜力。
