Ionic Liquids in Separation Science

Ionic Liquids Uncoiled: Critical Expert Overviews

Volumn , Issue , 2012, Pages 87-118

  Graham, Christa M ^a   Anderson, Jared L ^a  

^a UNIVERSITY OF TOLEDO   (United States)

Author keywords

CCC separation, and "elution extrusion"; Ionic liquids in GC, hydrogen bond basicity difference; Ionic liquids in separation science; Ionic liquids polymeric in chromatographic electrophoretic separations; Separation science and green processes, SFC in mobile phase

Indexed keywords

EID: 84886323957     PISSN: None     EISSN: None     Source Type: Book    
DOI: 10.1002/9781118434987.ch4     Document Type: Chapter

References (117)

1. Schellnhuber, H.J., Global warming: stop worrying, start panicking? Proc. Natl. Acad. Sci. U.S.A. 105(38), 14239-14240 (2008).
2. Rodríguez-Gil, J.L., Catalá, M., Alonso, S.G., Maroto, R.R., Valcárcel, Y., Segura, Y., Molina, R., Melero, J.A., and Martínez, F., Heterogeneous photo-fenton treatment for the reduction of pharmaceutical contamination in Madrid rivers and ecotoxicological evaluation by a miniaturized fern spores bioassay, Chemosphere 80(4), 381-388 (2010).
3. Müller, L., Mauthe, R.J., Riley, C.M., Andino, M.M., De Antonis, D., Beels, C., DeGeorge, J., De Knaep, A.G.M., Ellison, D., Fagerland, J.A., Frank, R., Fritschel, B., Galloway, S., Harpur, E., Humfrey, C.D.N., Jacks, A.S., Jagota, N., Mackinnon, J., Mohan, G., Ness, D.K., O'Donovan, M.R., Smith, M.D., Vudathala, G., and Yotti, L., A rationale for determining, testing, and controlling specific impurities in pharmaceuticals that possess potential for genotoxicity, Regul. Toxicol. Pharmacol. 44(3), 198-211 (2006).
4. Wilkes, J.S., A short history of ionic liquids-from molten salts to neoteric solvents, Green Chem. 4(2), 73-80 (2002).
5. Wilkes, J.S., Levisky, J.A., Wilson, R.A., and Hussey, C.L., Dialkylimidazolium chloroaluminate melts-a new class of room-temperature ionic liquids for electrochemistry, spectroscopy, and synthesis, Inorg. Chem. 21(3), 1263-1264 (1982).
6. Gale, R.J., and Osteryoung, R.A., Electrochemical reduction of pyridinium ions in ionic aluminum-chloride-alkylpyridinium halide ambient-temperature liquids, J. Electrochem. Soc. 127(10), 2167-2172 (1980).
7. Gale, R.J., and Osteryoung, R.A., Potentiometric investigation of dialuminum heptachloride formation in aluminum chloride 1-butylpyridinium chloride mixtures, Inorg. Chem. 18(6), 1603-1605 (1979).
8. Hurley, F.H., and Wier, T.P., Electrodeposition of metals from fused quaternary ammonium salts, J. Electrochem. Soc. 98(5), 203-206 (1951).
9. Wilkes, J.S., and Zaworotko, M.J., Air and water stable 1-ethyl-3-methylimidazolium based ionic liquids, J. Chem. Soc. Chem. Commun. 13, 965-967 (1992).
10. Fuller, J., Carlin, R.T., Delong, H.C., and Haworth, D., Structure of 1-ethyl-3-methylimidazolium hexafluorophosphate-model for room-temperature moltensalts, J. Chem. Soc. Chem. Commun. 3, 299-300 (1994).
11. Poole, C.F., The essence of chromatography, Elsevier Science B. V., Amsterdam (2003), p. 138.
12. Armstrong, D.W., He, L.F., and Liu, Y.S., Examination of ionic liquids and their interaction with molecules, when used as stationary phases in gas chromatography, Anal. Chem. 71(17), 3873-3876 (1999).
13. Abraham, M.H., Scales of solute hydrogen-bonding-their construction and application to physicochemical and biochemical processes, Chem. Soc. Rev. 22(2), 73-83 (1993).
14. Revelli, A.L., Mutelet, F., and Jaubert, J.N., Partition coefficients of organic compounds in new imidazolium based ionic liquids using inverse gas chromatography, J. Chromatogr. A 1216(23), 4775-4786 (2009).
15. Sprunger, L.M., Gibbs, J., Proctor, A., Acree, W.E., Abraham, M.H., Meng, Y., Yao, C., and Anderson, J.L., Linear free energy relationship correlations for room temperature ionic liquids: revised cation-specific and anion-specific equation coefficients for predictive applications covering a much larger area of chemical space, Ind. Eng. Chem. Res. 48(8), 4145-4154 (2009).
16. Mutelet, F., Revelli, A.L., Jaubert, J.N., Sprunger, L.M., Acree, W.E., Baker, G.A. Partition coefficients of organic compounds in new imidazolium and tetralkylammonium based ionic liquids using inverse gas chromatography, J. Chem. Eng. Data 55(1), 234-242 (2010).
17. Yao, C., and Anderson, J.L., Retention characteristics of organic compounds on molten salt and ionic liquid-based gas chromatography stationary phases, J. Chromatogr. A 1216(10), 1658-1712 (2009).
18. Vervoort, R.J.M., Debets, A.J.J., Claessens, H.A., Cramers, C.A., and de Jong, G.J., Optimisation and characterisation of silica-based reversed-phase liquid chromatographic systems for the analysis of basic pharmaceuticals, J. Chromatogr. A 897(1-2), 1-22 (2000).
19. Nawrocki, J., The silanol group and its role in liquid chromatography, J. Chromatogr. A 779(1-2), 29-71 (1997).
20. Berthod, A., and Carda-Broch, S., A new class of solvents for CCC: the room temperature ionic liquids, J. Liq. Chromatogr. Relat. Technol. 26(9-10), 1493-1508 (2003).
21. Marszall, M.P., and Kaliszan, R., Application of ionic liquids in liquid chromatography, Crit. Rev. Anal. Chem. 37(2), 127-140 (2007).
22. Shetty, P.H., Youngberg, P.J., Kersten, B.R., and Poole, C.F., Solvent properties of liquid organic salts used as mobile phases in microcolumn reversed-phase liquidchromatography, J. Chromatogr. 411, 61-79 (1987).
23. Waichigo, M.M., and Danielson, N.D., Ethylammonium formate as an organic solvent replacement for ion-pair reversed-phase liquid chromatography, J. Chromatogr. Sci. 44(10), 607-614 (2006).
24. Zheng, J., and Row, K.H., Effects of ionic liquid on the separation of 2-chlorophenol and 2, 4, 6-trichlorophenol in RP-HPLC, J. Chromatogr. Sci. 47(5), 392-395 (2009).
25. Xiao, X.H., Zhao, L., Liu, X., and Jiang, S.X., Ionic liquids as additives in high performance liquid chromatography-analysis of amines and the interaction mechanism of ionic liquids, Anal. Chim. Acta 519(2), 207-211 (2004).
26. Kaliszan, R., Marszall, M.P., Markuszewski, M.J., Baczek, T., and Pernak, J., Suppression of deleterious effects of free silanols in liquid chromatography by imidazolium tetrafluoroborate ionic liquids, J. Chromatogr. A 1030(1-2), 263-271 (2004).
27. He, L.J., Zhang, W.Z., Zhao, L., Liu, X., and Jiang, S.X., Effect of 1-alkyl-3-methylimidazolium-based ionic liquids as the eluent on the separation of ephedrines by liquid chromatography, J. Chromatogr. A 1007(1-2), 39-45 (2003).
28. Marszall, M.P., Baczek, T., and Kaliszan, R., Reduction of silanophilic interactions in liquid chromatography with the use of ionic liquids, Anal. Chim. Acta 547(2), 172-178 (2005).
29. Zhang, W.Z., He, L.J., Gu, Y.L., Liu, X., and Jiang, S.X., Effect of ionic liquids as mobile phase additives on retention of catecholamines in reversed-phase highperformance liquid chromatography, Anal. Lett. 36(4), 827-838 (2003).
30. Waichigo, M.M., and Danielson, N.D., Comparison of ethylammonium formate to methanol as a mobile-phase modifier for reversed-phase liquid chromatography, J. Sep. Sci. 29(5), 599-606 (2006).
31. Martín-Calero, A., Pino, V., Ayala, J.H., González, V., and Afonso, A.M., Ionic liquids as mobile phase additives in high-performance liquid chromatography with electrochemical detection: application to the determination of heterocyclic aromatic amines in meat-based infant foods, Talanta 79(3), 590-597 (2009).
32. Holbrey, J.D., Reichert, W.M., Nieuwenhuyzen, M., Sheppard, O., Hardacre, C., and Rogers, R.D., Liquid clathrate formation in ionic liquid-aromatic mixtures, Chem. Commun. 4, 476-477 (2003).
33. Zheng, J., and Row, K.H., Separation of guanine and hypoxanthine with some ionic liquids in RP-HPLC, Am. J. Appl. Sci. 3(12), 2160-2166 (2006).
34. Ruiz-Angel, M.J., Carda-Broch, S., and Berthod, A., Ionic liquids versus triethylamine as mobile phase additives in the analysis of beta-blockers, J. Chromatogr. A 1119(1-2), 202-208 (2006).
35. Pan, L., LoBrutto, R., Kazakevich, Y.V., and Thompson, R., Influence of inorganic mobile phase additives on the retention, efficiency and peak symmetry of protonated basic compounds in reversed-phase liquid chromatography, J. Chromatogr. A 1049(1-2), 63-73 (2004).
36. Berthod, A., Ruiz-Angel, M.J., and Huguet, S., Nonmolecular solvents in separation methods: dual nature of room temperature ionic liquids, Anal. Chem. 77(13), 4071-4080 (2005).
37. Sun, Y., Cabovska, B., Evans, C.E., Ridgway, T.H., and Stalcup, A.M., Retention characteristics of a new butylimidazolium-based stationary phase, Anal. Bioanal. Chem. 382(3), 728-734 (2005).
38. Van Meter, D.S., Sun, Y.Q., Parker, K.M., and Stalcup, A.M., Retention characteristics of a new butylimidazolium-based stationary phase. Part II: anion exchange and partitioning, Anal. Bioanal. Chem. 390(3), 897-905 (2008).
39. Qiu, H.D., Jiang, S.X., and Liu, X., N-methylimidazolium anion-exchange stationary phase for high-performance liquid chromatography, J. Chromatogr. A 1103(2), 265-270 (2006).
40. Wang, Q., Baker, G.A., Baker, S.N., and Colon, L.A., Surface confined ionic liquid as a stationary phase for HPLC, Analyst 131(9), 1000-1005 (2006).
41. Qiu, H.D., Jiang, S.X., Xia, L., and Zhao, L., Novel imidazolium stationary phase for high-performance liquid chromatography, J. Chromatogr. A 1116(1-2), 46-50 (2006).
42. Chaves, A.R., Júnior, G.C., and Queiroz, M.E.C., Solid-phase microextraction using poly(pyrrole) film and liquid chromatography with UV detection for analysis of antidepressants in plasma samples, J. Chromatogr. B 877(7), 587-593 (2009).
43. Brix, R., Bahi, N., de Alda, M.J.L., Farré, M., Fernandez, J.M., and Barceló, D., Identification of disinfection by-products of selected triazines in drinking water by LC-Q-ToF-MS/MS and evaluation of their toxicity, J. Mass Spectrom. 44(3), 330-337 (2009).
44. Endo, Y., Tagiri-Endo, M., Seo, H.S., and Fujimoto, K., Identification and quantification of molecular species of diacyl glyceryl ether by reversed-phase highperformance liquid chromatography with refractive index detection and mass spectrometry, J. Chromatogr. A 911(1), 39-45 (2001).
45. Savaliya, A.A., Shah, R.P., Prasad, B., and Singh, S., Screening of Indian aphrodisiac ayurvedic/herbal healthcare products for adulteration with sildenafil, tadalafil and/or vardenafil using LC/PDA and extracted ion LC-MS/TOF, J. Pharm. Biomed. Anal. 52(3), 406-409 (2010).
46. Silva, M.M., Bergamasco, J., Lira, S.P., Lopes, N.P., Hajdu, E., Peixinho, S., and Berlinck, R.G.S., Dereplication of bromotyrosine-derived metabolites by LCPDA-MS and analysis of the chemical profile of 14 aplysina sponge specimens from the Brazilian coastline, Aust. J. Chem. 63(6), 886-894 (2010).
47. Varandas, S., Teixeira, M.J., Marques, J.C., Aguiar, A., Alves, A., and Bastos, M.M.S.M., Glucose and fructose levels on grape skin: interference in Lobesia botrana behaviour, Anal. Chim. Acta 513(1), 351-355 (2004).
48. Koel, M., Physical and chemical properties of ionic liquids based on the dialkylimidazolium cation, Proc. Estonian Acad. Sci. Chem. 49(3), 145-155 (2000).
49. Conway, W.D., Counter-current chromatography: apparatus, theory, and applications, VCH Publishers, Inc., New York (1990), pp. 1-4.
50. Berthod, A., Ruiz-Angel, M.J., and Carda-Broch, S., Elution-extrusion countercurrent chromatography. Use of the liquid nature of the stationary phase to extend the hydrophobicity window, Anal. Chem. 75(21), 5886-5894 (2003).
51. Costa, F.D., and Leitao, G.G., Strategies of solvent system selection for the isolation of flavonoids by counter-current chromatography, J. Sep. Sci. 33(3), 336-347 (2010).
52. Du, Q.Z., Wu, C.J., Qian, G.J., Wu, P.D., and Ito, Y., Relationship between the flow-rate of the mobile phase and retention of the stationary phase in countercurrent chromatography, J. Chromatogr. A 835(1-2), 231-235 (1999).
53. Berthod, A., Ruiz-Angel, M.-J., and Carda-Broch, S., Ionic liquids as stationary phases in counter-current chromatography, in: Ionic liquids in chemical analysis, ed. M. Koel, CRC Press, Boca Raton (2009), pp. 211-228.
54. Berthod, A., and Carda-Broch, S., Use of the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate in counter-current chromatography, Anal. Bioanal. Chem. 380(1), 168-177 (2004).
55. Liu, R.M., Xu, L.L., Li, A.F., and Sun, A.L., Preparative isolation of flavonoid compounds from Oroxylum indicum by high-speed counter-current chromatography by using ionic liquids as the modifier of two-phase solvent system, J. Sep. Sci. 33(8), 1058-1063 (2010).
56. Xu, L.L., Li, A.F., Sun, A.L., and Liu, R.M., Preparative isolation of neomangiferin and mangiferin from Rhizoma anemarrhenae by high-speed counter-current chromatography using ionic liquids as a two-phase solvent system modifier, J. Sep. Sci. 33(1), 31-36 (2010).
57. Roth, M., Partitioning behaviour of organic compounds between ionic liquids and supercritical fluids, J. Chromatogr. A 1216(10), 1861-1880 (2009).
58. 2 to act as an antisolvent for ionic liquid/organic mixtures, J. Phys. Chem. B 111(18), 4837-4843 (2007).
59. Mekki, S., Wai, C.M., Billard, I., Moutiers, G., Yen, C.H., Wang, J.S., Ouadi, A., Gaillard, C., and Hesemann, P., Cu(II) extraction by supercritical fluid carbon dioxide from a room temperature ionic liquid using fluorinated beta-diketones, Green Chem. 7(6), 421-423 (2005).
60. Blanchard, L.A., and Brennecke, J.F., Recovery of organic products from ionic liquids using supercritical carbon dioxide, Ind. Eng. Chem. Res. 40(1), 287-292 (2001).
61. Schäfer, T., Rodrigues, C.M., Afonso, C.A.M., and Crespo, J.G., Selective recovery of solutes from ionic liquids by pervaporation-a novel approach for purification and green processing, Chem. Commun. 17, 1622-1623 (2001).
62. Earle, M.J., Esperança, J.M.S.S., Gilea, M.A., Lopes, J.N.C., Rebelo, L.P.N., Magee, J.W., Seddon, K.R., and Widegren, J.A., The distillation and volatility of ionic liquids, Nature 439(7078), 831-834 (2006).
63. Hu, R.L., Dai, X.J., Lu, Y.B., and Pan, Y.J., Preparative separation of isoquinoline alkaloids from Stephania yunnanensis by pH-zone-refining counter-current chromatography, J. Chromatogr. B 878(21), 1881-1884 (2010).
64. Duanmu, Q.P., Li, A.F., Sun, A.L., Liu, R.M., and Li, X.P., Semi-preparative highspeed counter-current chromatography separation of alkaloids from embryo of the seed of Nelumbo nucifera Gaertn by pH-gradient elution, J. Sep. Sci. 33(12), 1746-1751 (2010).
65. Lu, Y., Hu, R., Dai, Z., and Pan, Y., Preparative separation of anti-oxidative constituents from Rubia cordifolia by column-switching counter-current chromatography, J. Sep. Sci. 33, 2200-2205 (2010).
66. Cicek, S.S., Schwaiger, S., Ellmerer, E.P., and Stuppner, H., Development of a fast and convenient method for the isolation of triterpene saponins from Actaea racemosa by high-speed counter-current chromatography coupled with evaporative light scattering detection, Planta Med. 76(5), 467-473 (2010).
67. Yoon, K.D., and Kim, J., Application of centrifugal partition chromatography coupled with evaporative light scattering detection for the isolation of saikosaponins-a and -c from Bupleurum falcatum roots, J. Sep. Sci. 32(1), 74-78 (2009).
68. Cheng, Y.J., Liang, Q.L., Hu, P., Wang, Y.M., Jun, F.W., and Luo, G.A., Combination of normal-phase medium-pressure liquid chromatography and high-performance counter-current chromatography for preparation of ginsenoside-Ro from panax ginseng with high recovery and efficiency, Sep. Purif. Methods 73, 397-402 (2010).
69. Yao, S., Liu, R.M., Huang, X.F., and Kong, L.Y., Preparative isolation and purification of chemical constituents from the root of Adenophora tetraphlla by highspeed counter-current chromatography with evaporative light scattering detection, J. Chromatogr. A 1139(2), 254-262 (2007).
70. Liu, Z.L., Jin, Y., Shen, P.N., Wang, J., and Shen, Y.J., Separation and purification of verticine and verticinone from Bulbus Fritillariae Thunbergii by high-speed counter-current chromatography coupled with evaporative light scattering detection, Talanta 71(5), 1873-1876 (2007).
71. Qi, X.C., Ignatova, S., Luo, G.A., Liang, Q.L., Jun, F.W., Wang, Y.M., and Sutherland, I., Preparative isolation and purification of ginsenosides Rf, Re, Rd and Rb1 from the roots of Panax ginseng with a salt/containing solvent system and flow step-gradient by high performance counter-current chromatography coupled with an evaporative light scattering detector, J. Chromatogr. A 1217(13), 1995-2001 (2010).
72. Inoue, K., Hattori, Y., Hino, T., and Oka, H., An approach to on-line electrospray mass spectrometric detection of polypeptide antibiotics of enramycin for highspeed counter-current chromatographic separation, J. Pharm. Biomed. Anal. 51(5), 1154-1160 (2010).
73. Wybraniec, S., Jerz, G., Gebers, N., and Winterhalter, P., Ion-pair high-speed counter-current chromatography in fractionation of a high-molecular weight variation of acyl-oligosaccharide linked betacyanins from purple bracts of Bougainvillea glabra, J. Chromatogr. B 878(5-6), 538-550 (2010).
74. Anderson, J.L., and Armstrong, D.W., High-stability ionic liquids. A new class of stationary phases for gas chromatography, Anal. Chem. 75(18), 4851-4858 (2003).
75. Anderson, J.L., and Armstrong, D.W., Immobilized ionic liquids as high-selectivity/high-temperature/high-stability gas chromatography stationary phases, Anal. Chem. 77(19), 6453-6462 (2005).
76. Han, X., and Armstrong, D.W., Ionic liquids in separations, Acc. Chem. Res. 40(11), 1079-1086 (2007).
77. Huang, K., Han, X., Zhang, X., and Armstrong, D.W., PEG-linked geminal dicationic ionic liquids as selective, high-stability gas chromatographic stationary phases, Anal. Bioanal. Chem. 389(7-8), 2265-2275 (2007).
78. Breitbach, Z.S., and Armstrong, D.W., Characterization of phosphonium ionic liquids through a linear solvation energy relationship and their use as GLC stationary phases, Anal. Bioanal. Chem. 390(6), 1605-1617 (2008).
79. Payagala, T., Zhang, Y., Wanigasekara, E., Huang, K., Breitbach, Z.S., Sharma, P.S., Sidisky, L.M., and Armstrong, D.W., Trigonal tricationic ionic liquids: a generation of gas chromatographic stationary phases, Anal. Chem. 81(1), 160-173 (2009).
80. Juvet, R.S., and Wachi, F.M., Gas chromatographic separation of metal halides by inorganic fused salt substrates, Anal. Chem. 32, 290-291 (1960).
81. Hanneman, W.W., Spencer, C.F., and Johnson, J.F., Molten salt mixtures as liquid phases in gas chromatography, Anal. Chem. 32(11), 1386-1388 (1960).
82. Pacholec, F., Butler, H.T., and Poole, C.F., Molten organic salt phase for gas-liquidchromatography, Anal. Chem. 54(12), 1938-1941 (1982).
83. Qiu, H.D., Wang, L.C., Liu, X., and Jiang, S.X., Preparation and characterization of silica confined ionic liquids as chromatographic stationary phases through surface radical chain-transfer reaction, Analyst 134(3), 460-465 (2009).
84. Zhao, Q.C., and Anderson, J.L., Highly selective GC stationary phases consisting of binary mixtures of polymeric ionic liquids, J. Sep. Sci. 33(1), 79-87 (2010).
85. Seeley, J.V., Seeley, S.K., Libby, E.K., Breitbach, Z.S., and Armstrong, D.W., Comprehensive two-dimensional gas chromatography using a high-temperature phosphonium ionic liquid column, Anal. Bioanal. Chem. 390(1), 323-332 (2008).
86. Reid, V.R., Crank, J.A., Armstrong, D.W., and Synovec, R.E., Characterization and utilization of a novel triflate ionic liquid stationary phase for use in comprehensive two-dimensional gas chromatography, J. Sep. Sci. 31(19), 3429-3436 (2008).
87. Lambertus, G.R., Crank, J.A., McGuigan, M.E., Kendler, S., Armstrong, D.W., and Sachs, R.D., Rapid determination of complex mixtures by dual-column gas chromatography with a novel stationary phase combination and spectrometric detection, J. Chromatogr. A 1135(2), 230-240 (2006).
88. Siegler, W.C., Crank, J.A., Armstrong, D.W., and Synovec, R.E., Increasing selectivity in comprehensive three-dimensional gas chromatography via an ionic liquid stationary phase column in one dimension, J. Chromatogr. A 1217(18), 3144-3149 (2010).
89. Armstrong, D.W., Payagala, T., and Sidisky, L.M., The advent and potential impact of ionic liquid stationary phases in GC and GCxGC, LC GC North Am. 27(8), 596-605 (2009).
90. Anderson, J.L., Ding, J., Welton, T., and Armstrong, D.W., Characterizing ionic liquids on the basis of multiple solvation interactions, J. Am. Chem. Soc. 124(47), 14247-14254 (2002).
91. Anderson, J.L., Ding, R.F., Ellern, A., and Armstrong, D.W., Structure and properties of high stability geminal dicationic ionic liquids, J. Am. Chem. Soc. 127(2), 593-604 (2005).
92. Payagala, T., Huang, J., Breitbach, Z.S., Sharma, P.S., and Armstrong, D.W., Unsymmetrical dicationic ionic liquids: manipulation of physicochemical properties using specific structural architectures, Chem. Mater. 19(24), 5848-5850 (2007).
93. Zhao, Q., and Anderson, J.L., Highly selective GC stationary phases consisting of binary mixtures of polymeric ionic liquids, J. Sep. Sci. 33(1), 79-87 (2010).
94. Baltazar, Q.Q., Leininger, S.K., and Anderson, J.L., Binary ionic liquid mixtures as gas chromatography stationary phases for improving the separation selectivity of alcohols and aromatic compounds, J. Chromatogr. A 1182(1), 119-127 (2008).
95. Kim, Y.S., Choi, W.Y., Jang, J.H., Yoo, K.P., and Lee, C.S., Solubility measurement and prediction of carbon dioxide in ionic liquids, Fluid Phase Equilib. 228, 439-445 (2005).
96. 2 so soluble in imidazolium-based ionic liquids? J. Am. Chem. Soc. 126(16), 5300-5308 (2004).
97. 2 systems, J. Phys. Chem. B 105(12), 2437-2444 (2001).
98. 2, Nature 399(6731), 28-29 (1999).
99. Miyawaki, O., and Tatsuno, M., Lipase-catalyzed butanolysis of triolein in ionic liquid and selective extraction of product using supercritical carbon dioxide, J. Biosci. Bioeng. 105(1), 61-64 (2008).
100. 2 system at temperatures from 313 to 353 K and at pressures up to 16 MPa, J. Supercrit. Fluids 43(3), 430-437 (2008).
101. 2 system: measurement and LSER-based correlation, J. Phys. Chem. B 111(26), 7620-7625 (2007).
102. Planeta, J., and Roth, M., Solute partitioning between the ionic liquid 1-n-butyl-3-methylimidazolium tetrafluoroborate and supercrifical CO2 from capillarycolumn chromatography, J. Phys. Chem. B 109(31), 15165-15171 (2005).
103. Chou, F.M., Wang, W.T., and Wei, G.T., Using subcritical/supercritical fluid chromatography to separate acidic, basic, and neutral compounds over an ionic liquidfunctionalized stationary phase, J. Chromatogr. A 1216(16), 3594-3599 (2009).
104. Oda, R.P., and Landers, J.P., Introduction to capillary electrophoresis, in: Handbook of capillary electrophoresis, 2nd ed., ed. J.P. Landers, CRC Press, Boca Raton (1997), pp. 2-42.
105. Vaher, M., and Kaljurand, M., Ionic liquids as background electrolyte additives in capillary electrophoresis, in: Ionic liquids in chemical analysis, ed. M. Koel, CRC Press, Boca Raton (2009), p. 190.
106. Yanes, E.G., Gratz, S.R., Baldwin, M.J., Robison, S.E., and Stalcup, A.M., Capillary electrophoretic application of 1-alkyl-3-methylimidazolium-based ionic liquids, Anal. Chem. 73(16), 3838-3844 (2001).
107. Yanes, E.G., Gratz, S.R., and Stalcup, A.M., Tetraethylammonium tetrafluoroborate: a novel electrolyte with a unique role in the capillary electrophoretic separation of polyphenols found in grape seed extracts, Analyst 125(11), 1919-1923 (2000).
108. Mwongela, S.M., Numan, A., Gill, N.L., Agbaria, R.A., and Warner, I.M., Separation of achiral and chiral analytes using polymeric surfactants with ionic liquids as modifiers in micellar electrokinetic chromatography, Anal. Chem. 75(22), 6089-6096 (2003).
109. Yue, M.E., and Shi, Y.P., Application of 1-alkyl-3-methylimidazolium-based ionic liquids in separation of bioactive flavonoids by capillary zone electrophoresis, J. Sep. Sci. 29(2), 272-276 (2006).
110. François, Y., Varenne, A., Juillerat, E., Servais, A.C., Chiap, P., and Gareil, P., Nonaqueous capillary electrophoretic behavior of 2-aryl propionic acids in the presence of an achiral ionic liquid-a chemometric approach, J. Chromatogr. A 1138(1-2), 268-275 (2007).
111. Tian, Y., Feng, R., Liao, L.P., Liu, H.L., Chen, H., and Zeng, Z.R., Dynamically coated silica monolith with ionic liquids for capillary electrochromatography, Electrophoresis 29(15), 3153-3159 (2008).
112. López-Pastor, M., Simonet, B.M., Lendl, B., and Valcárcel, M., Ionic liquids and CE combination, Electrophoresis 29(1), 94-107 (2008).
113. Sherma, J., Planar chromatography, Anal. Chem. 82(12), 4895-4910 (2010).
114. B̧aczek, T., Marszall, M.P., Kaliszan, R., Walijewski, L., Makowiecka, W., Sparzak, B., Grzonka, Z., Wísniewska, K., and Juszczyk, P., Behavior of peptides and computer-assisted optimization of peptides separations in a normal-phase thinlayer chromatography system with and without the addition of ionic liquid in the eluent, Biomed. Chromatogr. 19(1), 1-8 (2005).
115. Santos, L.S., Haddad, R., Höehr, N.F., Pilli, R.A., and Eberlin, M.N., Fast screening of low molecular weight compounds by thin-layer chromatography and "on-spot" MALDI-TOF mass spectrometry, Anal. Chem. 76(7), 2144-2147 (2004).
116. Nichthauser, J., and Stepnowski, P., Retention mechanism of selected ionic liquids on a pentafluorophenylpropyl polar phase: investigation using RP-HPLC, J. Chromatogr. Sci. 47(3), 247-253 (2009).
117. Buszewski, B., Welerowicz, T., and Kowalkowski, T., Effect of chemically bonded stationary phases and mobile phase composition on beta-blockers retention in RP-HPLC, Biomed. Chromatogr. 23(3), 324-333 (2009).