eCite Digital Repository

An electrophoretic ion analyzer for on-site autonomous water monitoring


Liu, S and Pan, Z and Liang, Y and Li, F and Breadmore, MC and Zhang, M, An electrophoretic ion analyzer for on-site autonomous water monitoring, Journal of Chromatography A, 1637 Article 461791. ISSN 0021-9673 (2021) [Refereed Article]

Copyright Statement

© 2020 Elsevier B.V.

DOI: doi:10.1016/j.chroma.2020.461791


An on-site ion analyzer based on capillary electrophoresis with pressure-driven flow through injection and capacitively coupled contactless conductivity detection has been developed for field monitoring of cations and anions in environmental waters. Automated time-pressure based hydrodynamic injection provides stable pL-nL scale injection (RSD = 1.96%, n = 30). A mixture of 400 mM Bis-Tris, 400 mM MOPS and 2 mM 18-crown-6 is used as the background electrolyte to provide repeatable separations. A proprietary hydrophilic coated 25 μm id capillary is used to suppress the electroosmotic flow. Separations of anions (Cl-, NO3-, NO2-, SO42-, F- and PO43-) and cations (NH4+, K+, Na+, Ca2+ and Mg2+) are achieved by switching the polarity of the high voltage power supply in two individual runs. Signal fluctuations caused by the temperature or viscosity changes in on-site monitoring are corrected by on-line introduction of internal standards. RSDs of the migration time and the corrected peak height over ~35 h and 350 analysis cycles are < 4.06%. The LODs of inorganic ions are in the range of 2.1 μM (K+) to 6.8 μM (PO43-).  The feasibility for on-site water monitoring with this system has been validated by a standard Ion chromatography method with comparable results obtained.

Item Details

Item Type:Refereed Article
Keywords:capillary electrophoresis, on-site environmental monitoring, automated flow through injection, capacitively coupled contactless conductivity detection, analytical chemistry
Research Division:Chemical Sciences
Research Group:Analytical chemistry
Research Field:Separation science
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the chemical sciences
UTAS Author:Li, F (Mr Feng Li)
UTAS Author:Breadmore, MC (Professor Michael Breadmore)
UTAS Author:Zhang, M (Dr Min Zhang)
ID Code:143978
Year Published:2021
Web of Science® Times Cited:5
Deposited By:Chemistry
Deposited On:2021-04-13
Last Modified:2022-08-23

Repository Staff Only: item control page