| Ionic liquids (ILs) is a kind of new medium and soft functional materials, whichhave been developed in the recent years. Compared with other solvents, ILs have a lotof features, such as non-toxicity, low vapor pressure, non-flammability, goodconductivity, wide electrochemical window, low melting point, good thermal stability,ability to dissolve various organic and inorganic substances. ILs can be widely used asextraction solvents in the liquid-liquid extraction.However, the high viscosity, the high cost, easy loss in the extraction process, theslow mass transfer rate, the possible secondary pollution on the environment are themain disadvantages of the ILs. Therefore, when ILs are immobilized on the carriersand ILs are present in the form of a liquid film, mass transfer efficiency in theextraction process can be improved, and the amount of ILs can be reduced.In this thesis, the adsorbents immobilized with ILs, were used to extractpesticides and veterinary medicines.In the introduction, the history, sort, property and synthesis of ILs wereintroduced, and the application of ILs in analytical chemistry was summarized.In chapter2, the solvent (ionic liquid) impregnated resin (IL-SIR) was used asthe adsorbents for separation and enrichment of four herbicides (monolinuron,propazine, linuron and prebane) in water samples. The ionic liquid [C6MIM][PF6] wasimmobilized on Diaion HP20resin by immersing the resin in ethanol solutioncontaining [C6MIM][PF6]. The effect of extraction parameters, including pH value ofsample solution, salt concentration in sample and extraction time, and elution conditions, including the concentration of ethanol in elution solvent, the flow rate ofelution solvent and the ultrasonic power, were examined and optimized.100mg ofIL-SIR was accurately weighed and added into50mL of water sample. NaCl wasadded in the water sample and its concentration was10%. Then, the mixture wasstirred for60min. Thereafter, the IL-SIR was isolated from the solution by filteringwith filter paper. The obtained IL-SIR was placed in the elution column. The elutioncolumn was put in ultrasonic bath. The ultrasonic power was80W. Meantime, themicro-infusion pump was activated and the elution solvent (ethanol) was passedthrough the elution column at the flow rate of0.1mL min1. The target analytes and[C6MIM][PF6] were eluted with1.0mL of elution solvent. The eluate was injectedinto the HPLC system for analysis.The limits of detection and quantification for theanalytes were in the range of0.15～0.29μg L1and0.51～0.98μg L1, respectively.Six environmental water samples were analyzed and the analytical results weresatisfactory.In chapter3, an extraction method was developed for extracting fivesulfonamides (sulfamethoxazole, sulfadoxine, sulfaphenazole, sulfadimethoxine andsulfaquinoxaline) from fish by the matrix solid-phase dispersion (MSPD) using thesilica-supported ionic liquid (S-SIL) as the dispersion adsorbent. To immobilize the[C6MIM]Cl on the surface of the silica, the silica powder (pretreatment at150℃for3h) was immersed into methanol solution containing [C6MIM]Cl. After stirred for2.5h, the volatile components in the mixture were removed on a rotary evaporator.Then the resulting solution dried in air at60℃, leading to a white powder.1.0g offish sample was blended thoroughly with1.0g of S-SIL in an agate mortar for5minto obtain a homogeneous mixture. The homogeneous mixture was transferred into theMSPD column.1.0g of alumina-B was used as clean-up adsorbent,20mL ofdichloromethane was used as wash solvent and20mL of ethyl acetate was used aselution solvent. Then the eluate was evaporated to dryness and the residue wasdissolved in200μL of initial mobile phase. The resulting solution was referred to asanalytical solution and injected into the HPLC system for analysis. Some real sampleswere analyzed and the analytical results were satisfactory. The recoveries and relativestandard deviations of the five analytes are from86.4to113.2%and from1.51to5.87%, receptively. The LODs and LOQs range from3.98to4.16μg kg-1and from13.28to13.88μg kg-1, respectively. In chapter4, MSPD was applied for extracting six sulfonamides (sulfathiazole,sulfapyridine, sulfamerazine, sulfachloropyridane, sulfamethoxazole andsulfadimethoxine) from milk using the S-SIL as the dispersion adsorbent.1.0g ofmilk sample and1.5g of S-SIL were mixted in an agate mortar for5min to obtain ahomogeneous mixture. The homogeneous mixture was transferred into the MSPDcolumn.1.0g of alumina-B was usd as clean-up adsorbent,25mL ofdichloromethane was used as wash solvent and25mL of ethyl acetate was used aselution solvent. Then the eluate was evaporated to dryness and the residue wasdissolved in200μL of initial mobile phase. The resulting solution was referred to asanalytical solution and injected into the HPLC system for analysis. The recoveries ofsulfathiazole, sulfapyridine, sulfamerazine, sulfachloropyridane, sulfamethoxazoleand sulfadimethoxine are98.9～108.3%,97.2～106.9%,93.6～102.3%,98.4～107.6%,97.3～104.2%,98.1～103.8%, receptively and the relative standarddeviations are1.55～4.27%,1.44～4.51%,1.29～3.91%,1.39～6.86%,1.26～6.48%,1.62～7.53%, receptively. The LODs and LOQs are1.89～2.90μg kg1and6.32～9.64μg kg1, respectively.In chapter5, MSPD compled with homogeneous liquid–liquid microextraction(HLLME) was developed for extracting six herbicides (chlortoluron, monolinuron,propazine, linuron and prebane) in rice. To immobilize the [C6MIM]Cl on the surfaceof the silica, the silica powder (pretreatment at500℃for24h) was immersed intomethanol solution containing [C6MIM]Cl. After stirred for2.5h, the volatilecomponents in the mixture were removed on a rotary evaporator. Then the resultingsolution dried in air at60℃, leading to a white powder.1.0g of rice sample wasblended thoroughly with0.5g of S-SIL in an agate mortar for5min to obtain ahomogeneous mixture. The homogeneous mixture was transferred into the MSPDcolumn.0.5g of S-SIL was used as the dispersion adsorbent and10mL of water wesused as elution solvent. The0.0018mol of NH4PF6was added into10mL waterelution solvent. After1min, the minxture was centrifuged for5min at4000prm.54μL of [C6MIM] PF6was deposited on the bottom of the tube. The [C6MIM] PF6wasdiluted with50μL of acetonitrile. The resulting solution was referred to as analyticalsolution and injected into the HPLC system for analysis. The recoveries and relativestandard deviations of the five analytes are from95.5to118.7%and from0.93to5.45%, receptively. The LODs and LOQs range from1.01to1.64μg kg-1and from 3.38to5.46μg kg-1, respectively.
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