School of the Environment, Jiangsu University, Zhenjiang 212013, China.
Anal Chim Acta. 2011 Jan 31;685(2):138-45. doi: 10.1016/j.aca.2010.11.033. Epub 2010 Nov 23.
Ionic liquid-salt aqueous two-phase flotation (ILATPF) is a novel, green, non-toxic and sensitive samples pretreatment technique. ILATPF coupled with high-performance liquid chromatography (HPLC) was developed for the analysis of chloramphenicol, which combines ionic liquid aqueous two-phase system (ILATPS) based on imidazolium ionic liquid (1-butyl-3-methylimidazolium chloride, [C(4)mim]Cl) and inorganic salt (K(2)HPO(4)) with solvent sublation. In ILATPF systems, phase behaviors of the ILATPF were studied for different types of ionic liquids and salts. The sublation efficiency of chloramphenicol in [C(4)mim]Cl-K(2)HPO(4) ILATPF was influenced by the types of salts, concentration of K(2)HPO(4) in aqueous solution, solution pH, nitrogen flow rate, sublation time and the amount of [C(4)mim]Cl. Under the optimum conditions, the average sublation efficiency is up to 98.5%. The mechanism of ILATPF contains two principal processes. One is the mechanism of IL-salt ILATPS formation, the other is solvent sublation. This method was practical when applied to the analysis of chloramphenicol in lake water, feed water, milk, and honey samples with the linear range of 0.5-500 ng mL(-1). The method yielded limit of detection (LOD) of 0.1 ng mL(-1) and limit of quantification (LOQ) of 0.3 ng mL(-1). The recovery of CAP was 97.1-101.9% from aqueous samples of environmental and food samples by the proposed method. Compared with liquid-liquid extraction, solvent sublation and ionic liquid aqueous two-phase extraction, ILATPF can not only separate and concentrate chloramphenicol with high sublation efficiency, but also efficiently reduce the wastage of IL. This novel technique is much simpler and more environmentally friendly and is suggested to have important applications for the concentration and separation of other small biomolecules.
离子液体-盐双水相浮选（ILATPF）是一种新型的、绿色的、无毒的和灵敏的样品预处理技术。将离子液体-盐双水相体系（ILATPS）与高效液相色谱（HPLC）相结合，建立了离子液体-盐双水相浮选-高效液相色谱法（ILATPF-HPLC）用于氯霉素的分析。该方法以基于咪唑类离子液体（1-丁基-3-甲基咪唑氯盐，[C4mim]Cl）和无机盐（磷酸氢二钾，K2HPO4）的离子液体双水相体系为基础，结合溶剂浮选。在 ILATPF 体系中，研究了不同类型的离子液体和盐对 ILATPF 相行为的影响。氯霉素在 [C4mim]Cl-K2HPO4 ILATPF 中的浮选效率受盐的类型、水溶液中 K2HPO4 的浓度、溶液 pH 值、氮气流速、浮选时间和 [C4mim]Cl 的用量的影响。在最佳条件下，平均浮选效率高达 98.5%。ILATPF 的机制包含两个主要过程。一是离子液体-盐离子液体双水相体系的形成机制，二是溶剂浮选机制。该方法可用于湖水、饮用水、牛奶和蜂蜜样品中氯霉素的分析，线性范围为 0.5-500ng/mL。该方法的检出限（LOD）为 0.1ng/mL，定量限（LOQ）为 0.3ng/mL。与液-液萃取、溶剂浮选和离子液体双水相萃取相比，该方法对环境水样和食品样品中的 CAP 回收率为 97.1%-101.9%。与液-液萃取、溶剂浮选和离子液体双水相萃取相比，ILATPF 不仅可以以高浮选效率分离和浓缩氯霉素，而且还可以有效地减少离子液体的浪费。这种新技术更加简单、环保，有望在其他小分子的浓缩和分离方面得到重要应用。
