ESTONIAN ACADEMY
PUBLISHERS
eesti teaduste
akadeemia kirjastus
cover
Proceedings of the Estonian Academy of Sciences. Chemistry
Ionic liquids as background electrolyte additives and coating materials in capillary electrophoresis; pp. 187–198
PDF | https://doi.org/10.3176/chem.2007.4.03

Authors
Merike Vaher, Maria Borissova, Mihkel Koel, Mihkel Kaljurand
Abstract

Now that many scientific investigations focus on ionic liquids (IL) to establish their potential in different chemical processes, their application for the separation of various classes of compounds in capillary electrophoresis has also been recognized. ILs have been used as background electrolytes in aqueous and non-aqueous capillary electrophoresis for the separation of a number of different analyte types providing both control of the electroosmotic flow and the charging of analytes. Besides this ILs are used as micelle-forming compounds and capillary wall modifiers, as well as separation media additives in NACE for contactless conductivity detection.

References

1. Walden, P. Ueber die Molekulargrösse und elektrische Leitfähigkeit einiger geschmolzenen Salze. Bull. Acad. Imper. Sci., 1914, 405–422.

2. Koel, M. Ionic liquids in chemical analysis. Crit. Rev. Anal. Chem., 2005, 35, 3177–3192. 
https://doi.org/10.1080/10408340500304016

3. Pandey, S. Analytical applications of room-temperature ionic liquids: A review of recent efforts. Anal. Chim. Acta, 2006, 556, 38–45. 
https://doi.org/10.1016/j.aca.2005.06.038

4. Cabovska, B. & Stalcup, A. Ionic liquids in chromatography and capillary electrophoresis. J. Liq. Chromatogr. Relat. Technol., 2004, 27, 1443–1459.
https://doi.org/10.1081/JLC-120030611

5. Chen, X. & Qi, S. The capillary electrophoresis based on ionic liquids. Curr. Anal. Chem., 2006, 2, 411–419. 
https://doi.org/10.2174/157341106778520535

6. Bączek, T., Marszałł, M. P., Kaliszan, R., Walijewski, Ł., Makowiecka, W., Sparzak, B., Grzonka, Z., Wiśniewska, K. & Juszczyk, P. Behavior of peptides and computer-assisted optimization of peptides separations in a normal-phase thin-layer chromatography system with and without the addition of ionic liquid in the eluent. Biomed. Chromatogr., 2005, 19, 1–8. 
https://doi.org/10.1002/bmc.405

7. Vaher, M., Koel, M. & Kaljurand, M. Non-aqueous capillary electrophoresis in acetonitrile using ionic-liquid buffer electrolytes. Chromatographia, 2001, 53, S302–S306. 
https://doi.org/10.1007/BF02490346

8. Vaher, M., Koel, M. & Kaljurand, M. Ionic liquids as electrolytes for nonaqueous capillary electrophoresis. Electrophoresis, 2002, 23, 426–430. 
https://doi.org/10.1002/1522-2683(200202)23:3<426::AID-ELPS426>3.0.CO;2-8

9. Vaher, M., Koel, M. & Kaljurand, M. Application of 1-alkyl-3methylimidazolium based ionic liquids in non-aqueous capillary electrophoresis. J. Chromatogr. A, 2002, 979, 27–32. 
https://doi.org/10.1016/S0021-9673(02)01499-1

10. Vaher, M. & Koel, M. Separation of polyphenolic compounds extracted from plant matrices using capillary electrophoresis. J. Chromatogr. A, 2003, 990, 225–230. 
https://doi.org/10.1016/S0021-9673(02)02013-7

11. Kuldvee, R., Vaher, M., Koel, M. & Kaljurand, M. Heteroconjugation-based capillary electro­phoretic separation of phenolic compounds in acetonitrile and propylene carbonate. Electrophoresis, 2003, 24, 1627–1634. 
https://doi.org/10.1002/elps.200305378

12. Miller, J. L., Shea, D. & Khaledi, M. G. Separation of acidic solutes by nonaqueous capillary electrophoresis in acetonitrile-based media. Combinated effects of deprotonation and hetero­conjugation. J. Chromatogr. A, 2000, 888, 251–266. 
https://doi.org/10.1016/S0021-9673(00)00467-2

13. Vaher, M. & Koel, M. Specific background electrolytes for nonaqueous capillary electro­phoresis. J. Chromatogr. A, 2005, 1068, 83–88. 
https://doi.org/10.1016/j.chroma.2004.10.028

14. Borissova, M., Gorbatšova, J., Ebber, A., Kaljurand, M., Koel, M. & Vaher, M. Nonaqueous CE using contactless conductivity detection and ionic liquids as BGE in ACN. Electrophoresis, 2007, 28, 3600–3605. 
https://doi.org/10.1002/elps.200700067

15. Saito, R. M., Neves, C. A., Lopes, F. S., Blanes, L., Brito-Neto, J. G. A. & do Lago, C. Monitor­ing the electroosmotic flow in capillary electrophoresis using contactless con­ductivity detection and thermal marks. Anal. Chem., 2007, 79, 215–223. 
https://doi.org/10.1021/ac0615293

16. François, Y., Varenne, A., Juillerat, E., Servais, A.-C., Chiap, P. & Gareil, P. Nonaqueous capillary electrophoretic behavior of 2-aryl propionic acids in the presence of anchiral ionic liquid. J. Chromatogr. A, 2007, 1138, 268–275. 
https://doi.org/10.1016/j.chroma.2006.10.063

17. François, Y., Zhang, K., Varenne, A. & Gareil, P. New integrated measurements protocol using capillary electrophoresis instrumentation for the determination of viscosity, conductivity and absorbance of ionic liquid–molecular solvent mixtures. Anal. Chim. Acta, 2006, 562, 164–170. 
https://doi.org/10.1016/j.aca.2006.01.036

18. Tholey, A. & Heinzle, E. Ionic (liquids) matrices for matrix-assisted laser desorption/ionization mass spectrometry – applications and perspectives. Anal. Bioanal. Chem., 2006, 386, 24–37. 
https://doi.org/10.1007/s00216-006-0600-5

19. Yanes, E. G., Gratz, S. R., Baldwin, M. J., Robison, S. E. & Stalcup, A. M. Capillary electro­phoretic application of 1-alkyl-3-methylimidazolium-based ionic liquids. Anal. Chem., 2001, 73, 3838–3844. 
https://doi.org/10.1021/ac010263r

20. Jiang, T.-F., Gu, Y.-L., Liang, B., Li, J.-B., Shi, Y.-P. & Ou, Q.-Y. Dynamically coating the capillary with 1-alkyl-3-methylimidazolium-based ionic liquids for separation of basic proteins by capillary electrophoresis. Anal. Chim., Acta, 2003, 479, 249–254. 
https://doi.org/10.1016/S0003-2670(02)01537-4

21. Cabovska, B., Kreishman, G. P., Wassell, D. F. & Stalcup, A. M. Capillary electrophoretic and nuclear magnetic resonance studies of interactions between halophenols and ionic liquid or tetraalkylammonium cations. J. Chromatogr. A, 2003, 1007, 179–187. 
https://doi.org/10.1016/S0021-9673(03)00985-3

22. Yu, L., Qin, W. & Li, S. F. Y. Ionic liquids as additives for separation of benzoic acid and chloro‑phenoxy acid herbicides by capillary electrophoresis. Anal. Chim. Acta, 2005, 547, 165–171. 
https://doi.org/10.1016/j.aca.2005.05.047

23. Wang, Y. L., Hu, Z. B. & Yuan, Z. B. Ionic liquid and HP-β-CD modified capillary zone electro­phoresis to separate hyperoside, luteolin and chlorogenic acid. Chin. Chem. Lett., 2006, 17, 231–234.

24. Tian, K., Qi, S., Cheng, Y., Chen, X. & Hu, Z. Separation and determination of lignans from seeds of Shisandra species by micellar electrokinetic capillary chromatography using ionic liquids as modifier. J. Chromatogr. A, 2005, 1078, 181–187. 
https://doi.org/10.1016/j.chroma.2005.05.018

25. Marszałł, M. P., Markuszewski, M. J. & Kaliszan, R. Separation of nicotic acid and its structural isomers using 1-ethyl-3-methylimidazolium ionic liquids as a buffer additive by capillary electrophoresis. J. Pharm. Biomed. Analysis, 2006, 41, 329–332. 
https://doi.org/10.1016/j.jpba.2005.11.013

26. Jiang, T. F., Wang, Y. H. & Lv, Z. H. Dynamic coating of a capillary with room-temperature ionic liquids for the separation of amino acids and acid drugs by capillary electrophoresis. J. Anal. Chem., 2006, 61, 1108–1112. 
https://doi.org/10.1134/S1061934806110128

27. Qi, S., Li, Y., Deng, Y., Cheng, Y., Chen, X. & Hu, Z. Simultaneous determination of bioactive flavone derivatives in Chinese herb extraction by capillary electrophoresis used different electrolyte systems – borate and ionic liquids. J. Chromatogr. A, 2006, 1109, 300–306. 
https://doi.org/10.1016/j.chroma.2006.01.045

28. Schnee, V. P., Baker, G. A., Rauk, E. & Palmer, C. P. Electrokinetic chromatographic characteriza­tion of novel pseudo-phases based on N-alkyl-N-methylpyrrolidinium ionic liquid type surfactants. Electrophoresis, 2006, 27, 4141–4148. 
https://doi.org/10.1002/elps.200600268

29. Mwongela, S. M., Siminialayi, N., Fletcher, K. A. & Warner, I. M. A comparison of ionic liquids to molecular organic solvents as additives for chiral separations in micellar electro­kinetic chromatorgraphy. J. Sep. Sci.,2007, 30, 1334–1342. 
https://doi.org/10.1002/jssc.200600455

30. Carey, M. C. & Small, D. M. Micellar properties of dihydroxy and trihydroxy bile salts. J. Colloid Interf. Sci., 1969, 31, 382–396. 
https://doi.org/10.1016/0021-9797(69)90181-7

31. Qin, W. & Li, S. F. Y. An ionic liquid coating for determination of sildenaftyl and UK-103, 320 in human serum by capillary zone electrophoresis – ion trap mss spectrometry. Electro­phoresis, 2002, 23, 4110–4116. 
https://doi.org/10.1002/elps.200290028

32. Qin, W. & Li, S. F. Y. Electrophoresis of DNA in ionic liquid coated capillary. Analyst, 2003, 128, 37–41. 
https://doi.org/10.1039/b208724c

33. Qin, W., Wei, H. & Li, S. F. Y. 1,3-Dialkylimidazolium-based room-temperature ionic liquids as background electrolyte and coating material in aqueous capillary electrophoresis. J. Chromatogr. A, 2003, 985, 447–454. 
https://doi.org/10.1016/S0021-9673(02)01844-7

34. Qin, W. & Li, S. F. Y. Determination of ammonium and metal ions by capillary electro­phoresis-potential gradient detection using ionic liquids as background electrolyte and covalent coating reagent. J. Chromatogr. A, 2004, 1048, 253–256. 
https://doi.org/10.1016/S0021-9673(04)01208-7
https://doi.org/10.1016/j.chroma.2004.07.048

35. Borissova, M., Koel, M. & Kaljurand, M. Ionic liquids for silica modification: assessment by capillary zone electrophoresis. In Ionic Liquids: Not Just Solvents Anymore (Rogers, R. D. & Seddon, K. R., eds). ACS, Washington, DC, in press.
 

36. Borissova, M., Vaher, M., Koel, M. & Kaljurand, M. Capillary zone electrophoresis on chemically bonded imidazolium based salts. J. Chromatogr. A, 2007, 1160, 320–325. 
https://doi.org/10.1016/j.chroma.2007.04.032

Back to Issue

Back issues