Abstract
The potentialities of new ionic liquids (ILs) based on choline were evaluated as an electrophoretic medium in capillary electrophoresis for the analysis of alkaline and alkaline earth cations (Li+, K+, Na+, Cs+, Mg2+, Ba2+, Ca2+, and Sr2+) with indirect UV detection. Two types of capillaries were tested: an untreated fused silica and fused silica coated with a film of polyvinylalcohol. The coated capillary proved to be the best adapted for the metal ions studied. Moreover, it appeared that the nature of the ionic liquid anion influenced the baseline stability, and the bis(trifluoromethylsulfonyl) imide (NTf2 −) anion seemed to be the most efficient. These preliminary studies led us to synthesize a new ionic liquid, 2-hydroxy-N,N,N-trimethyl-1-phenylethanaminium NTf2 (phenylcholine NTf2). This liquid was able to act as the running electrolyte and probe, generating the background signal in indirect UV light and consequently simplifying the electrophoretic medium. Excellent baseline stability, good reproducibility, as well as good sensitivity of detection were obtained with this new ionic liquid. Thus, 510,000 plates/meter for Li+ with 40 mM IL were successfully obtained. The optimal concentration of IL was 20 mM with a detection limit ranging from 28 μg L−1 for Li+ to 1,000 μg L−1 for Cs+. This method (phenylcholine NTf2 with polyvinylalcohol capillary) was applied to analyze different commercial source and mineral waters. Finally, the potentiality of this ionic liquid in nonaqueous capillary electrophoresis was explored. The use of phenylcholine NTf2 with a fused silica capillary, in pure methanol medium and in the presence of acetic acid, made it possible to obtain separation selectivity different from that obtained in aqueous medium.
Similar content being viewed by others
References
Hjerten S (1967) Chromatogr Rev 9:122–219
Vrouwe EX, Luttge R, Olthuis W, Van den Berg A (2006) J Chromatogr A 1102:287–293
Pacáková V, Coufal P, Štulík K (1999) J Chromatogr A 834:257–275
Fukushi K, Takeda S, Chayama K, Wakida S (1999) J Chromatogr A 834:349–362
Timerbaev AR (2004) Electrophoresis 25:4008–4031
François Y, Zhang K, Varenne A, Gareil P (2006) Anal Chim Acta 562:164–170
Jiang TF, Gu YL, Liang B, Li JB, Shi YP, Ou QY (2003) Anal Chim Acta 479:249–254
Marszałł MP, Markuszewski MJ, Kalistan R (2006) J Pharm Biomed Anal 41:329–332
Qi S, Cui S, Chen X, Hu Z (2004) J Chromatogr A 1059:191–198
Laamanen PL, Busi S, Lathinen M, Matilainen R (2005) J Chromatogr A 1095:164–171
Qi S, Li Y, Deng Y, Cheng Y, Chen X, Hu Z (2006) J Chromatogr A 1109:300–306
Yanes EG, Gratz SR, Baldwin MJ, Robison SE, Stalcup AM (2001) Anal Chem 73:3838–3844
Mo H, Zhu L, Xu W (2008) J Sep Sci 31:2470–2475
Wu X, Wei W, Su Q, Xu L, Chen G (2008) Electrophoresis 29:2356–2362
Tian K, Wang Y, Chen Y, Chen X, Hu Z (2007) Talanta 72:587–593
Mwongela SM, Numan A, Gill NL, Agbaria RA, Warnar IM (2003) Anal Chem 75:6089–6096
Rizvi SAA, Shamsi SA (2006) Anal Chem 78:7061–7069
François Y, Varenne A, Juillerat E, Villemin D, Gareil P (2007) J Chromatogr A 1155:134–141
Qin W, Li SFY (2002) Electrophoresis 23:4110–4116
Qin W, Li SFY (2003) Analyst 128:37–41
Borissova M, Vaher M, Koel M, Kaljurand M (2007) J Chromatogr A 1160:320–325
Vaher M, Koel M, Kaljurand M (2001) Chromatographia 53:S302–S306
Vaher M, Koel M, Kaljurand M (2002) Electrophoresis 23:426–430
Vaher M, Koel M, Kaljurand M (2002) J Chromatogr A 979:27–32
Qin W, Wei H, Li SFY (2003) J Chromatogr A 985:447–454
Qin W, Li SFY (2004) J Chromatogr A 1048:253–256
Vaher M, Koel M (2005) J Chromatogr A 1068:83–88
R Lide D (2005) CRC handbook of chemistry and physics. CRC, Boca Raton FL
Maraca JF (2004) Chimie des solides. EDP Sciences Les Ulis
Senet P (1997) Chem Phys Lett 275:527–532
Martin RB (2002) Inorg Chim Acta 339:27–33
Tamisier-Karolak SL, Le Potier I, Barlet O, Czok M (1999) J Chromatogr A 852:487–498
ICH Guideline: Q2B, Validation of Analytical Procedures: Methodology, 1995
François C, Morin Ph, Dreux M (1995) J Chromatogr A 706:535–553
Salimi-Moosavi H, Cassidy RM (1996) J Chromatogr A 749:279–272
Acknowledgments
This research was supported by the National Centre for Scientific Research (CNRS), ACI “Nouvelles technologies et capteurs”. Dr H. Krajian would like to thank the Atomic Energy Commission of Syria (P.O. Box 6091, Damascus, Syria) for the doctoral fellowship.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Mofaddel, N., Krajian, H., Villemin, D. et al. New ionic liquid for inorganic cations analysis by capillary electrophoresis: 2-hydroxy-N,N,N-trimethyl-1-phenylethanaminium bis(trifluoromethylsulfonyl)imide (phenylcholine NTf2). Anal Bioanal Chem 393, 1545–1554 (2009). https://doi.org/10.1007/s00216-008-2582-y
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00216-008-2582-y