您当前的位置:首页 > TAG信息列表 > 离子液体

  • [Wiley数据库][2012] Application of ionic liquid-based microwave-assisted extraction of malachite green and crystal violet from water samples
  • 更新时间:2016-03-21;信息类型:期刊文章
  • A simple, environmentally friendly and efficient technique, ionic liquid-based microwave-assisted extraction was first used to determine malachite green and crystal violet from water samples coupled to high-performance liquid chromatography. The key parameters influencing extraction efficiency were investigated, such as the type of ionic liquids, the volume of ionic liquid, extraction time, and so on. Under the optimum conditions, good reproducibility of the extraction performance was obtained (relative standard deviation, 1.0% for malachite green and 5.9% for crystal violet, n=5). Good linearity (0.10-25 µg L-1) was observed with correlation coefficients between 0.9991 and 0.9964. The detection limits of malachite green and crystal violet were 0.080 and 0.030 µg Lí1, respectively. The proposed method had been successfully applied to determine malachite green and crystal violet in real water samples with recoveries ranging from 95.4 to 102.8%. Compared with the previous technologies, the proposed method required less extraction time (2 min), and provided lower detection limits and higher enrichment factors. Moreover, there was no volatile and hazardous organic solvents released. Based on these simple, environmentally friendly, rapid and highly efficient results, the proposed approach provides a new and promising alternative for simultaneously extracting trace amounts of MG and CV from water samples.
  • 链接地址:http://www.ionicliquid.org/download/c-articles/2016-03-21/344.html
  • [Wiley数据库][2012]Preliminary extration of tannins by 1-butyl-3-methylimidazole bromide and its subsequent removal from Galla chinensis extract using macroporous resins
  • 更新时间:2016-03-21;信息类型:期刊文章
  • In recent years, Ionic Liquids have become increasingly attractive as “green solvents” used in the extraction of bioactive compounds from natural plant. However, the separation of ionic liquid from the target compounds was difficult, due to their low vapour pressure and high stabilities. In our study, ionic liquid-based ultrasonic and microwave-assisted extraction was used to obtain the crude tannins, then the macroporous resin adsorption technology was further employed to purify the tannins and remove the ionic liquid from crude extract. The results showed that XDA-6 had higher separation efficiency than other tested resins, and the equilibrium experimental data were well-fitted to Langmuir isotherms. Dynamic adsorption and desorption were performed on XDA-6 packed in glass columns to optimize the separation process. The optimum conditions as follows: the ratio of column height to diameter bed was 1:8, flow rate 1BV/h, 85% ethanol was used as eluant while the elution volume was 2BV. Under the optimized conditions, the adsorption and desoption rate of tannins in XDA-6 were 94.81% and 91.63% respectively. The content of tannins was increased from 70.24% in Galla chinensis extract to 85.12% with a recovery of 99.06%. The result of UPLC-MS/MS analysis showed that [bmim]Br could be removed from extract.
  • 链接地址:http://www.ionicliquid.org/download/c-articles/2016-03-21/343.html
  • [Wiley数据库][2012]Ionic liquid-based dispersive liquid–liquid microextraction with back-extraction coupled with capillary electrophoresis to determine phenolic compounds
  • 更新时间:2016-03-21;信息类型:期刊文章
  • Ionic liquid (IL) based dispersive liquid–liquid microextraction (DLLME) with backextraction coupled with capillary electrophoresis ultraviolet detection was developed to determine four phenolic compounds (bisphenol-A, β-naphthol, α-naphthol, 2, 4-dichlorophenol) in aqueous cosmetics. The developed method was used to preconcentrate and clean up the four phenolic compounds including two steps. The analytes were transferred into room temperature ionic liquid (1-octyl-3-methylimidazolium hexafluorophosphate, [C8MIM][PF6]) rich-phase in the first step. In the second step, the analytes were back-extracted into the alkaline aqueous phase. The effects of extraction parameters, such as type and volume of extraction solvent, type and volume of disperser, extraction and centrifugal time, sample pH, salt addition, and concentration and volume of NaOH in back-extraction were investigated. Under the optimal experimental conditions, the preconcentration factors were 60.1 for bisphenol-A, 52.7 for β-naphthol, 49.2 for α-naphthol, and 18.0 for 2, 4-dichlorophenol. The limits of detection for bisphenol-A, β-naphthol, α-naphthol and 2, 4-dichlorophenol were 5, 5, 8, and 100 ng mL−1, respectively. Four kinds of aqueous cosmetics including toner, soften lotion, make-up remover, and perfume were analyzed and yielded recoveries ranging from 81.6% to 119.4%. The main advantages of the proposed method are quick, easy, cheap, and effective.
  • 链接地址:http://www.ionicliquid.org/download/c-articles/2016-03-21/342.html
  • [Wiley数据库][2012]Influence of ionic liquids as electrolyte additives on chiral separation of dansylated amino acids by using Zn(II) complex mediated chiral ligand exchange capillary electrophoresis
  • 更新时间:2016-03-20;信息类型:期刊文章
  • In this work, investigation of the comparative influence of diverse ionic liquids as electrolyte additives on the chiral separation of dansylated amino acids by using Zn(II)-L-arginine complex mediated chiral ligand exchange capillary electrophoresis was conducted. It has been found that not only the varied substituted group number, but also the alkyl chain length of the substituted group on imidazole ring in the structure of ionic liquids show different influence on chiral separation of the analytes in the chiral ligand exchange capillary electrophoresis system, which could be understood by their direct influence on electroosmotic flow. Meanwhile, the variation of anion in the structure of ionic liquids displayed remarkably changed performance and the ionic liquids with Cl- showed the most obvious promoting effect on the chiral separation performance. Among the investigated seven ionic liquids, 1-butyl-3-methylimidazolium chloride was validated to be the proper electrolyte additive in the chiral ligand exchange capillary electrophoresis system. Further, it has been observed that 1-butyl-3-methylimidazolium chloride also has obviously promotive effect on the labeling performance. The results have demonstrated that the ionic liquids with different structures have important relation to their performance in chiral ligand exchange capillary electrophoresis and to their labeling efficiency in dansylation of the analytes.
  • 链接地址:http://www.ionicliquid.org/download/c-articles/2016-03-20/341.html
 441   首页 上一页 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 下一页 尾页