Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, Tehran, Iran.
J Sep Sci. 2011 Jan;34(1):98-106. doi: 10.1002/jssc.201000624.
Dynamic three-phase hollow fiber liquid-liquid-liquid microextraction (HF-LLLME) based on two immiscible organic solvents, with automated movement of organic acceptor phase to facilitate mass transfer was introduced for the first time. Polycyclic aromatic hydrocarbons were used as model compounds and extracted from water and soil samples. The extraction involved filling an 8 cm length of hollow fiber with 25 μL of organic acceptor solvent using a microsyringe, followed by impregnation of the pores in the fiber wall with n-dodecane. The fiber was then immersed in 20 mL of aqueous sample solution. During extraction, the organic acceptor phase was repeatedly moved in the lumen of the hollow fiber by movement of the syringe plunger controlled by programmable syringe pump. Following this microextraction, 2 μL of organic acceptor phase was injected into gas chromatography-flame ionization detector. This new technique provided up to 554-fold preconcentration of the analytes under the optimized conditions. Good repeatabilities (with RSDs ≤8.4%) were obtained. Detection limits were in the range of 0.2-0.5 μg/L. The utilization of the proposed method for extraction of the polycyclic aromatic hydrocarbons from different real samples (such as water and soil samples) also gave good precision and recovery.
首次提出了一种基于两种互不相溶有机溶剂的动态三相中空纤维液-液-液微萃取（HF-LLLME）方法，该方法通过有机接受相的自动移动来促进传质。多环芳烃被用作模型化合物，从水和土壤样品中提取。萃取过程包括用微量进样器在 8 厘米长的中空纤维内填充 25 μL 的有机接受溶剂，然后用正十二烷浸渍纤维壁的孔。然后将纤维浸入 20 mL 水相样品溶液中。在萃取过程中，通过可编程注射器泵控制的注射器柱塞的移动，将有机接受相反复移动到中空纤维的内腔中。经过微萃取后，将 2 μL 的有机接受相注入气相色谱-火焰离子化检测器。在优化条件下，该新技术可将分析物的预浓缩倍数提高到 554 倍。获得了良好的重复性（RSDs ≤8.4%）。检测限范围为 0.2-0.5 μg/L。该方法用于从不同实际样品（如水和土壤样品）中提取多环芳烃，也具有良好的精密度和回收率。
