| With the development of society and technology, people’s awareness aboutdifferent chemical substances is more and more comprehensive and we can use themwith high proficiency. However, the abuse of chemical substances will lead to harm.For example, the addition of sex hormones to cosmetics is beneficial to promotinghair growth, eliminating wrinkles, increasing skin elasticity and preventing skin fromaging, but long-term use of these cosmetics can cause metabolic disorders of thehuman body and even the occurrence of cancer. Again, for example the use oftriazine herbicides in agricultural domain can control broadleaf and grassy weeds,but the residue around the environment and in the agricultural products will do harmto human health causing cancers, birth defects and interruption of hormone functions.Therefore, the development of some reliable and simple analytical methods is veryimportant.Liquid-phase microextraction is a new sample preparation technique which wasintroduced in the mid-1990s. The method simplifies the procedure and reduces thetime associated with conventional sample clean-up and analyte enrichment. Theextraction method has some advantages in respect of simple operation, micro-literlevel of organic solvent and high extraction efficiency. Ionic liquids are a group of“green” organic solvents, which have some unique physical-chemical properties, such as high thermal stability, low vapor pressure, structure adjustability andmoderate dissolvability of water, inorganic compounds and organic compounds.Therefore, ILs are widely studied and applied in many fields. As a barrier of organicsolvent, hollow fiber membrane contributes to separate the sample matrix and theacceptor phase and also prevents the acceptor phase from contaminating. Themicropores on the polypropylene material provide addition filtration to prevent largeparticles from entering the extraction solvent and reduce potential interferences.Therefore, hollow fiber liquid-phase microextraction is suitable for the directanalysis of complex matrix.In this study, Ils were used as extraction solvents. The ionic liquid-based hollowfiber liquid-phase microextraction coupled with high performance liquidchromatography was applied for the determination of sexual hormones in cosmeticsand triazine herbicides in vegetables.Determination of sexual hormones in cosmetics by magnetically stirringextraction bar liquid-liquid microextraction was described. The experimentalparameters, including the type of ionic liquid, the immersion time of the hollow fiber,the pH value of sample solution, the concentration of NaCl and the extraction timewere evaluated. When [C8MIM][PF6] was selected as extraction solvent and theextraction time was40min, the extraction recoveries were highest. The detectionlimits for19-nortestosterone (nandrolone), testosterone, estrone,17-α-hydroxyprogesterone, medroxyprogesterone, megestrol acetate, progesterone,and testosterone propionate (androlin) are0.94,0.79,0.95,0.91,0.94,0.95,0.92,and1.01ng mL-1, respectively. When applying the present method to the analysis ofreal cosmetics, the recoveries of the analytes ranged from91.3%to106.2%andrelative standard deviations were lower than5.47%.Determination of triazine herbicide residues in vegetables based on ionic liquidsolvent bar microextraction high performance liquid chromatography was described.The experimental parameters including the type of ionic liquid, the number ofsolvent bar, the pH value of sample solution, ionic strength and extraction time were evaluated by a univariate method and orthogonal screening. When [C6MIM][PF6]was used as extraction solvent and the extraction time was40min, the recoveries ofanalytes were satisfactory. The detection limits for atraton, desmetryn, atrazine,terbumeton, terbuthylazine, dimethametryn, and dipropetryn were9.95,1.14,0.93,1.15,1.17,1.19, and0.87μg kg-1, respectively. When applying the present method tothe analysis of vegetable samples, the recoveries of the analytes ranged from82.1%to119.7%and relative standard deviations were lower9.65%. |
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