TY - JOUR
T1 - Highly sensitive chiral analysis in capillary electrophoresis with large-volume sample stacking with an electroosmotic flow pump
AU - Kawai, Takayuki
AU - Koino, Hiroshi
AU - Sueyoshi, Kenji
AU - Kitagawa, Fumihiko
AU - Otsuka, Koji
N1 - Funding Information:
T.K. thanks the support from the research fellowships of the Japan Society for Promotion of Science (JSPS) for young scientists. This development was supported in part by SENTAN, JST. This research was supported in part by the Global COE Program “Integrated Materials Science (#B-09)” of the Ministry of Education, Culture, Sports, Science and Technology, Japan, administrated by JSPS.
PY - 2012/7/13
Y1 - 2012/7/13
N2 - To improve the sensitivity in chiral analysis by capillary electrophoresis without loss of optical resolution, application of large-volume sample stacking with an electroosmotic flow pump (LVSEP) was investigated. Effects of the addition of cyclodextrin (CD) into a running solution on the LVSEP preconcentration was theoretically studied, where the preconcentration efficiency and effective separation length would be slightly increased if the effective electrophoretic velocity (v ep,eff,BGS) of the analytes was decreased by interacting with CD. In LVSEP-CD-modified capillary zone electrophoresis (CDCZE) and LVSEP-CD electrokinetic chromatography with reduced v ep,eff,BGS, up to 1000-fold sensitivity increases were achieved with almost no loss of resolution. In LVSEP-CD-modified micellar electrokinetic chromatography of amino acids with increased v ep,eff,BGS, a 1300-fold sensitivity increase was achieved without much loss of resolution, indicating the versatile applicability of LVSEP to many separation modes. An enantio-excess (EE) assay was also carried out in LVSEP-CDCZE, resulting in successful analyses of up to 99.6% EE. Finally, we analyzed ibuprofen in urine by desalting with a C 18 solid-phase extraction column. As a typical result, 250ppb ibuprofen was well concentrated and optically resolved with 84.0-86.6% recovery in LVSEP-CDCZE, indicating the applicability of LVSEP to real samples containing a large amount of unnecessary background salts.
AB - To improve the sensitivity in chiral analysis by capillary electrophoresis without loss of optical resolution, application of large-volume sample stacking with an electroosmotic flow pump (LVSEP) was investigated. Effects of the addition of cyclodextrin (CD) into a running solution on the LVSEP preconcentration was theoretically studied, where the preconcentration efficiency and effective separation length would be slightly increased if the effective electrophoretic velocity (v ep,eff,BGS) of the analytes was decreased by interacting with CD. In LVSEP-CD-modified capillary zone electrophoresis (CDCZE) and LVSEP-CD electrokinetic chromatography with reduced v ep,eff,BGS, up to 1000-fold sensitivity increases were achieved with almost no loss of resolution. In LVSEP-CD-modified micellar electrokinetic chromatography of amino acids with increased v ep,eff,BGS, a 1300-fold sensitivity increase was achieved without much loss of resolution, indicating the versatile applicability of LVSEP to many separation modes. An enantio-excess (EE) assay was also carried out in LVSEP-CDCZE, resulting in successful analyses of up to 99.6% EE. Finally, we analyzed ibuprofen in urine by desalting with a C 18 solid-phase extraction column. As a typical result, 250ppb ibuprofen was well concentrated and optically resolved with 84.0-86.6% recovery in LVSEP-CDCZE, indicating the applicability of LVSEP to real samples containing a large amount of unnecessary background salts.
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U2 - 10.1016/j.chroma.2012.02.001
DO - 10.1016/j.chroma.2012.02.001
M3 - Article
C2 - 22386259
AN - SCOPUS:84862560914
VL - 1246
SP - 28
EP - 34
JO - Journal of Chromatography A
JF - Journal of Chromatography A
SN - 0021-9673
ER -