| Sample pretreatment is the key link in the sample analysis. Its aim is to reduce the interference of impurities on the targets, and concentrate trace amounts of analytes in the sample. Recently, with the development of chemical analysis techniques, sample pretreatment techniques has been developed in the direction of simple, rapid, sensitive, consuming less organic reagents and environment-friendly. SPME is a solvent-free extraction technique that incorporates sample extraction, purification and concentration into a single procedure. It overcomes traditional extraction methods’shortcomings, such as needing complicated operation or consuming large amounts of organic solvents. So, it has good development prospects. SPME techniques include stir bar sorptive extraction, in-tube solid phase microextraction, and so on. Polymer monolith microextraction (PMME) technology is developed on the basis of in-tube solid phase microextraction. Its surface properties can be controlled through the introduction of different types of functional groups, so it avoids the limitation of fewer extraction coating types in stir bar sorptive extraction. In addition, the monolith column of PMME is of adjustable pore structure, large specific surface area, good permeability and fast mass transfer velocity. Therefore, it also overcomes in-tube solid phase microextraction’s disadvantage of low extraction efficiency. Molecularly imprinted polymer monolith microextraction not only has MIP’s high selectivity, but also has PMME’s solvent-free advantages. As a result, it is a high recognized and environmentally friendly sample pretreatment technique.In this thesis, several different modes of SPME including polymer monolith microextraction (PMME) and molecular imprinted polymer monolith microextraction (MIPMME) in combination with high-performance liquid chromatography (HPLC) were used for the residue detection of certain pesticides in real environmental samples and Pharmaceuticals in biological samples. The main contents and the results are listed as follows:1. A method of poly (hydroxypropyl methacrylate-ethylene glycol dimethacrylate) monolith microextraction coupled with HPLC was developed for the determination of three fungicides (azoxystrobin, diethofencarb and pyrimethanil) in environmental water samples. To obtain the best extraction efficiency, factors affecting the extraction effiency such as sample flow rate, sample pH, extraction volume, desorption solvent type, volume, and desorption flow rate were investigated. Under the optimized conditions, the linear range was3-1000ng mL"1, the intra-day and inter-day precision were in the range of2.4%-3.1%and4.9%-6.3%. The method was demonstrated to be simple, consuming less organic solvents and was successfully applied for the analysis of three fungicides in real water samples.2. Poly (hydroxypropyl methacrylate-ethylene glycol dimethacrylate) capillary monolith microextraction coupled with HPLC was used to determin residue ketoconazole and econazole nitrate in human serum. Several parameters affecting the experiments such as sample flow rate, matix pH, sample volume, elution volume and flow rate were investigated. Under the optimal conditions, the limits of detection of ketoconazole and econazole nitrate were1.2μg L-1and2.1μg L-1. The proposed method was successfully used for the determination of antifungal agents in human serum.3. An azoxystrobin molecularly imprinted monolith was synthesized in a micropipette tip, then, molecularly imprinted polymer monolith microextraction coupled with HPLC was used for the detection of azoxystrobin in environmental water and juice samples. In order to obtain the best extraction efficiency, several parameters affecting experiments such as sample flow rate, sample volume,luent type, eluent volume and the eluent flow rate were investigated. Under the optimized conditions, the proposed method was applied for the decermination of azoxystrobin in real water and grape juice samples. |
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