| In recent years, ionic liquids have been developed rapidly and applied to the extraction and separation because of their excellent properties, such as wally miscibility, fine thermostability, diversity and designability. It can be used to prepare stable functional materials with multiple mechanism of action that would solve some traditional problems.Phenolic environmental estrogens are a kind of exogenous environmenttal chemicals that can induce the bad influence of the endocrine system of humans and animals. On account of their complex composition and low concentration in sample matrix, the pretreatment or enrichment methods before instrumental analysis are particularly essential. Pressurized capillary electrochromatography coupled to amperometric detection is a microseparation technique possessed both high selectivity.high separation efficiency of capillary electrochromatography (CEC) and high sensitivity of amperometric detector (AD), which provides an ideals analytical method for the detection of trace amounts of phenolic environmental estrogens. Capillary chromatographic column is the important factor that determin the selectivity and separation efficiency of analysis method. In this paper, new types of ionic liquid functionalized monolithic columns have been developed for extraction and separation, the extraction mode and separation mechanism of phenolic estrogen was discussed. Coupled with pCEC-AD, ionic liquid functionalized monolithic columns were successfully applied for the separation and enrichment of typical phenolic estrogens. Thesis includes the following three parts:1、Capillary electrochromatography and its principle, its related hyphenated detection techniques, especially amperometric detection and the principle, as well as capillary monolithic column were overviewed. The development and application of organic polymer monolith and ionic liquid in separation and extraction were demonstrated. The research content and significance of this thesis were briefly stated.2、A novel organic polymer monolithic column was prepared using imidazole ionic liquid as functional monomer through in-situ free radical copolymerization. Several factors that have impact on the column performance were investigated, including the proportion of monomer, porogens and polymerization temperature. The column performance was evaluated by investigating the retention behavior of alkylbenzenes, polyaromatic hydrocarbon, nucleoside substances and phenolic estrogens. Under the optimized conditions, the column efficiency for separation of alkylbenzenes is up to 72000-83000 N/m. No obvious tailing was observed. The prepared monolith column is stable and batch reproducible (RSD<5.0%, n= 3), which has good application prospect in the field of environmental and biological analysis.3、For the first time, an imidazole ionic liquid modified polymer microextraction column was synthesized by in situ polymerization. It was used to develop a PMME the enrichment method for three typical phenolic estrogens bisphenol A, 4-n-nonylphenol and 4-t-octylphenol. Some paramaters that affect the microextraction process were optimized, including sample extraction flow rate, extraction volume, pH of sample solution. Under the optimal conditions, a coupling method of PMME with pCEC-AD has been developed and appied to the analysis of three phenolic estrogens in aquatic product. Three substances were completely separated within 12 min, with a linear range of 0.01～5.0 mg/L. The detection limit (S/N=3) were 0.005-0.020 mg/L, and the mean recoveries were 76.1% to 96%. This method provides technical reference for high sensitive detection of phenolic estrogens in food and environment. |
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