Ionic liquids in chromatographic and electrophoretic techniques: toward additional improvements in the separation of natural compounds.
Due to their unique properties, in recent years, ionic liquids (ILs) have been largely investigated in the field of analytical chemistry. Particularly during the last sixteen years, they have been successfully applied in the chromatographic and electrophoretic analysis of value-added compounds extracted from biomass. Considering the growing interest in the use of ILs in this field, this critical review provides a comprehensive overview on the improvements achieved using ILs as constituents of mobile or stationary phases in analytical techniques, namely in capillary electrophoresis and its different modes, in high performance liquid chromatography, and in gas chromatography, for the separation and analysis of natural compounds. The impact of the IL chemical structure and the influence of secondary parameters, such as the IL concentration, temperature, pH, voltage and analysis time (when applied), are also critically addressed regarding the achieved separation improvements. Major conclusions on the role of ILs in the separation mechanisms and the performance of these techniques in terms of efficiency, resolution and selectivity are provided. Based on a critical analysis of all published results, some target-oriented ILs are suggested. Finally, current drawbacks and future challenges in the field are highlighted. In particular, the design and use of more benign and effective ILs as well as the development of integrated (and thus more sustainable) extraction-separation processes using IL aqueous solutions are suggested within a green chemistry perspective.
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
Belinda
B
Soares
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
Helena
H
Passos
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
Carmen S R
CSR
Freire
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
João A P
JAP
Coutinho
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
Armando J D
AJD
Silvestre
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
Mara G
MG
Freire
J Chromatogr A. 1999 Jul 2;848(1-2):523-7
10427766
Analyst. 2000 Nov;125(11):1919-23
11193077
Anal Chem. 2001 Aug 15;73(16):3838-44
11534705
Anal Chem. 1992 Dec 1;64(23):2981-4
1463219
J Chromatogr A. 2004 Dec 3;1059(1-2):191-8
15628141
J Chromatogr A. 2005 Jun 17;1078(1-2):181-7
16007996
Biomed Chromatogr. 2006 Mar;20(3):294-300
16138295
Anal Chem. 2005 Oct 1;77(19):6453-62
16194112
J Chromatogr A. 2005 Nov 18;1095(1-2):164-71
16275297
J Chromatogr A. 2006 Jan 27;1103(2):265-70
16325829
J Chromatogr A. 2006 Mar 24;1109(2):300-6
16464459
J Sep Sci. 2006 Feb;29(2):272-6
16524102
J Chromatogr A. 2006 Sep 1;1125(2):182-8
16781718
Anal Chem. 2006 May 1;78(9):2892-2902
16802464
J Chromatogr A. 2006 Oct 6;1129(2):304-7
16952364
J Chromatogr A. 2007 Jan 26;1140(1-2):56-62
17141255
Anal Bioanal Chem. 2007 Jun;388(4):889-99
17492276
J Chromatogr Sci. 2007 May-Jun;45(5):256-62
17555633
Talanta. 2007 Apr 30;72(2):587-93
19071659
Molecules. 2009 Jun 11;14(6):2127-34
19553886
Int J Mol Sci. 2009 Jun 04;10(6):2591-610
19582220
J Sep Sci. 2009 Oct;32(20):3550-4
19764054
J Sep Sci. 2009 Dec;32(23-24):4220-6
19937963
Talanta. 2010 Jan 15;80(3):1292-7
20006090
Anal Chim Acta. 2010 Feb 19;661(1):1-16
20113709
J Phys Chem A. 2010 Mar 25;114(11):3744-9
20235600
Molecules. 2010 Apr 05;15(4):2405-26
20428052
Int J Mol Sci. 2010 May 25;11(5):2229-40
20559512
J Chromatogr B Analyt Technol Biomed Life Sci. 2010 Aug 15;878(24):2243-8
20638917
Anal Chim Acta. 2010 Sep 16;677(2):162-8
20837183
Talanta. 2010 Dec 15;83(2):582-90
21111178
Chem Commun (Camb). 2011 Feb 21;47(7):1994-6
21234468
J Phys Chem B. 2011 Apr 14;115(14):4033-41
21425809
Electrophoresis. 2011 Apr;32(9):1068-73
21449068
J Chromatogr A. 2011 May 20;1218(20):3056-63
21450294
Anal Chem. 2011 Oct 15;83(20):7947-54
21902214
J Chromatogr A. 2011 Nov 25;1218(47):8480-9
21999917
Anal Chim Acta. 2012 Feb 10;714:20-37
22244134
Anal Chim Acta. 2012 Feb 17;715:19-41
22244164
Anal Chem. 2012 Mar 20;84(6):2805-10
22339647
Electrophoresis. 2012 Apr;33(7):1182-90
22539321
J Chromatogr A. 2012 Sep 14;1255:130-44
22621883
Chem Soc Rev. 2012 Jul 21;41(14):4966-95
22692625
Anal Chim Acta. 2013 Mar 12;767:148-54
23452799
J Chromatogr A. 2013 Dec 6;1319:160-5
24188995
Anal Chem. 2014 Jan 7;86(1):262-85
24205989
J Chromatogr A. 2014 Aug 29;1357:147-57
24786657
Phys Chem Chem Phys. 2014 Oct 21;16(39):21340-8
25179181
J Sep Sci. 2015 Feb;38(3):374-80
25447425
Green Chem. 2014 Dec;16(12):4786-4815
25516718
Green Chem. 2015 Jul 1;17(7):3948-3963
26379471
J Chromatogr A. 2015 Nov 13;1420:1-15
26463427
ACS Sustain Chem Eng. 2015 Oct 5;3(10):2558-2565
28255528