Capacitively coupled contactless conductivity detection with dual top-bottom cell configuration for microchip electrophoresis.

Abstract

An optimized capacitively coupled contactless conductivity detector for microchip electophoresis is presented. The detector consists of a pair of top-bottom excitation electrodes and a pair of pickup electrodes disposed onto a very thin plastic microfluidic chip. The detection cell formed by the electrodes is completely encased and shielded in a metal housing. These approaches allow for the enhancement of signal coupling and extraction from the detection cell that result in an improved signal-to-noise-ratio and detection sensitivity. The improved detector performance is illustrated by the electrophoretic separation of six cations (NH(4) (+), K(+), Ca(2+), Na(+), Mg(2+), Li(+)) with a detection limit of approximately 0.3 microM and the analysis of the anions (Br(-), Cl(-), NO(2) (-), NO(3) (-), SO(4) (2-), F(-)) with a detection limit of about 0.15 microM. These LODs are significantly improved compared with previous reports using the conventional top-top electrode geometry. The developed system was applied to the analysis of ions in bottled drinking water samples.

DOI: 10.1002/elps.200900578

Cite this paper

@article{Mahabadi2010CapacitivelyCC, title={Capacitively coupled contactless conductivity detection with dual top-bottom cell configuration for microchip electrophoresis.}, author={Kambiz Ansari Mahabadi and Isabel Rodr{\'i}guez and Chee Yeow Lim and Devendra K. Maurya and Peter C. Hauser and Nico F de Rooij}, journal={Electrophoresis}, year={2010}, volume={31 6}, pages={1063-70} }