| With the continuous development of our industry as well as the improvement of people’s livingstandards, more and more attention has been paid to the problem of environmental pollution, foodsafety and human health. Meanwhile, the determination problems of all kinds of organic pollutantsalso get great attention. At present, with the development of modern technology, analyticalinstruments have been able to meet the testing requirements of various compounds. Therefore, thesample pretreatment technology is very importent. This paper provides an overview of the samplepretreatment technology and testing equipments for organic pollutants in the environment and foodsamples. The equilibrium dialysis method and fluorescence quenching method were applied to studythe interaction among some kinds of pollutants and protein. A method was developed for analyzingbenzene series in fish by gas chromatography-mass spectroscopy (GC–MS), which was using matrixremoval method with aqueous two-phase system (ATPS) for preparing samples. And the samplepretreatment of aqueous two phase extraction technique and modified QuEChERS method wereused for the determination of three CBs in aquatic product.The paper was divided into five sections:Part one: This paper introduced the types of organic pollutants, function and potential hazardsand content and significance.Part two：A novel method was developed for analyzing benzene series in fish by gaschromatography-mass spectroscopy (GC–MS), which was using matrix removal method withaqueous two-phase system (ATPS) of acetonitrile–K2HPO4–H2O for preparing samples. Theinteraction of protein with benzene series were investigated using the equilibrium dialysis method.Meanwhile, the influence of protein, fat and other matrices on extraction of benzene series from fishsamples was also discussed. The results of equilibrium dialysis indicated that the combinationbetween benzene series and protein was very strong. In φ (acetonitrile)80%(the volume fraction ofacetonitrile) aqueous solution, a slow but full protein denaturation takes place, which would cause thedissociating of benzene series combined with protein. The matrix removal method with ATPS wasapplied to real fish sample and the results shown that the extraction efficiency of matrix removal method with ATPS was higher. The spiked recoveries by the proposed method, matrix removalmethod withATPS, were81.4~97.8%, and the limits of detection were in the range of1.1~4.3ng/g.Part three：Anovel method for the analysis of three chlorobenzene compounds(CBs:1,3-DCB;1,2-DCB;1,2,4-TCB) in fish samples, based on modified QuEChERS（Quick, Easy, Cheap,Effective, Rugged and Safe）approach is reported. The QuEChERS method was modified byreplacing the traditionnal acetonitrile with acetone aqueous solution. In this paper, the interactionbetween CBs and FSA and the effect of different concentration of acetone solution on proteindenaturation were detailed investigated by fluorescence spectrometry and rayleigh scatteringrespectively. The results showed that the binding constants KBbetween CBs and FSA were largerthan104L/mol, which implies CBs strongly bound with FSA. Meanwhile, the concentration ofacetone aqueous solution from70%to100%can cause protein denatured in different degree.Theinfluence of protein and other matrices were also discussed. It suggested that protein influenced onextraction of CBs. In dealing with the actual fish samples, it could obtained a better extractionefficiency with φ(acetone)90%(the volume fraction of acetone) aqueous solution as extractant.Because a slow but full protein denaturation takes place in the φ(acetone)90%aqueous solution,which would cause the dissociating of CBs combined with protein. The spiked recoveries by theproposed method were80.4~118.3%, and the limits of detection were2.4,7.3and2.6ng/g,respectively.Part four：Small molecular water-miscible organic solvent, such as acetone can be used to formaqueous two-phase system for extraction of analytes in the presence of salts. Just based on it, theacetone-salt-H2O system was developed for the determination of chlorobenzene compounds (CBs)in aquatic products coupled with gas chromatography-mass spectroscopy. In this article, theinteraction between CBs and FSA was detailed investigated by fluorescence spectrometry. Theresults showed that the binding constants KBbetween CBs and FSA were larger than104L/mol,which implies CBs strongly bound with FSA. Meanwhile, the influence of different concentration ofacetone-water solution and protein or fat on extraction of CBs from aquatic products was alsodiscussed. It suggested that protein influenced on extraction of CBs and it could obtained a betterextraction efficiency with φ(acetone)90%(the volume fraction of acetone) aqueous solution as extraction solvent. In the φ (acetone)90%aqueous solution, a slow but full protein denaturation takesplace, and the extraction solvent could fully contact with the CBs, obtaining higher extractionefficiency. This method was used for the ditermination of CBs in fish and Shrimp samples, with thespiked recoveries were77.0%~116.3%and82.4%~109.4%, respectively. The limits of detectionwere2.4,7.3and2.6ng/g, espectively.Part five: A novel method for the analysis of eight organochlorine residues in fish samples, basedon the use of isopropanol-K2HPO4-H2O system followed by gas chromatography (GC–ECD) isreported. The results showed that protein had some influence on the extraction of organochlorine. Inφ (isopropanol)80%(the volume fraction of isopropanol) aqueous solution, a slow but full proteindenaturation takes place, which would cause the dissociating of organochlorine combined withprotein. This resulted in the high extraction efficiency of organochlorine from fish sample. Thismethod was used for the ditermination of organochlorine in fish sample, with the spiked recoveriesand the limits of detection were78.6%~104.2%and0.10~0.39ng/g, respectively. |
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