Analytical and Bioanalytical Chemistry

, Volume 411, Issue 5, pp 1067–1073 | Cite as

Synergistic coupling of in-line single-drop microextraction and on-line large-volume sample stacking for capillary electrophoresis/mass spectrometry

  • Jihye Kim
  • Kihwan Choi
  • Doo Soo ChungEmail author
Research Paper


Single-drop microextraction (SDME) and large-volume sample stacking using an electroosmotic flow pump (LVSEP) were coupled with capillary electrophoresis/mass spectrometry (CE/MS) for sample cleanup and preconcentration. Without filtration or centrifugation of a soil sample containing debris, SDME using a pentanol acceptor drop was directly applied to the sample. After SDME, a large volume of the enriched pentanol extract was injected and further concentrated by LVSEP. For the drop formation in SDME and the sample matrix removal in LVSEP, a run buffer vial was temporarily placed to the electrospray tip, without any physical modification of the CE/MS interface. This method enabled the double preconcentration by SDME and LVSEP, achieving 600~1300-fold enrichments of anionic analytes including pesticide and herbicide compounds to provide limits of detection in the range of 0.4~0.8 ppb in soil.

Graphical abstract


Capillary electrophoresis-/mass spectrometry (CE/MS) Single-drop microextraction (SDME) Large-volume sample stacking using an electroosmotic flow pump (LVSEP) Sample preparation Soil 


Funding information

This work was supported by the National Research Foundation of Korea (NRF-2016R1A2B2011878, NRF-2017M2A8A5014710, and NRF-2017K1A3A1A67016126).

Compliance with ethical standards

This research did not involve human participants or animals.

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Nuclear Chemistry Research DivisionKorea Atomic Energy Research InstituteDaejeonSouth Korea
  2. 2.Division of Chemical and Medical MetrologyKorea Research Institute of Standards and ScienceDaejeonSouth Korea
  3. 3.Department of ChemistrySeoul National UniversitySeoulSouth Korea

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