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In order to meeting the demand of instrument analysis, people proposed columnchromatography, supercritical fluid technology, accelerated solvent extraction, solid-phasemicroextraction, liquid phase microextractionin on the traditional extraction method whichincluded soxhlet extraction, resin-rich, solid phase extraction, membrane extractiontechnology, microwave-assisted extraction technology, ultrasonic extraction technology.The common features of these techniques were less solvent, fast processing speed, easyautomation, known as green technology. Based on a review of the technology, liquid phasemicroextraction were studied systematically in this paper.Liquid phase microextraction (LPME) was developed as a new sample pretreatmenttechnology recently, in which sampling, extraction and enrichment completed in onestep.The technology has some features such as less organic solvent consumption, simpleoperation, time saving and it is an environmental friendly pretreatment technology. Thispaper mainly studies the application of LPME in fatty acid analysis.The main research in this paper are as followings:A new method was developed to determining the content of citric acid in soft drinksby the solvent bar microextraction coupled with HPLC. The factors of affecting theextraction efficiency were optimized. The optimum microextraction conditions are asfollowings: three tributyl phosphate was as the extractant, extraction time was25min,stirring rate was1000r/min, donor phase pH was2.0, acceptor phase pH was12.0. Underthe optimized extraction cinditions, the enrichment factors was22, there was good linearfrom5μ g/mL to200μg/mL in standard cure, the precision was5.4%, the detection limitwas0.16μ g/mL, the repertability in the actual samples were93.7%,90.4%.Two-phase hollow fiber liquid phase microextraction and HPLC were applid todetermine conjugated linoleic acid in sesame. The chromatographic conditions wereoptimized and extractant pH, extraction time, stirring rate and other factors effecting theextraction efficiency were observed, and the influence of various factors to liquid phase microextraction were described. the optimum experimental conditions of the systemare as followings: KOH solution in which pH was11.0was as the extractant, extractiontime was30min, stirring rate was1000r/min. Under the optimized extraction conditions,the enrichment factors was12, there was good linear from2.5μ g/mL to500μ g/mL instandard cure, the precision was7.4%, the detection limit was0.17μg/mL, therepertability in the actual samples were94.7%,89.6%,81.5%.Using KOH as the extractant, two-phase hollow fiber liquid phase microextractioncoupled with high performance liquid chromatography was used to determinatione thecontent of erucic acid in rapeseed oil. The chromatographic conditions were optimized.The effects of the factors such as extractant pH, extraction time, stirring rate and so on wasobserved. The optimum conditions were determined, the extraction and enrichment oferucic acid was achieved. The optimum conditions are as followings: the detectionwavelength was200nm, the pH of mobile phase was6.0, the content of methanol was40%, the injection volume was5μ L, the pH of extraction was12.0, extraction time was15,stirring rate was800r/min. Under the optimized extraction cinditions, the enrichmentfactors was8.5, there was good linear from20μ g/mL to500μ g/mL in standard cure, theprecision was3.4%, the detection limit was0.43μg/mL, the repertability in the actualsamples were82.1%,85.4%,86.5%.
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