Limits of miniaturization: Assessing ITP performance in sub-micron and nanochannels

Kjeld G. H. Janssen; Jiajie Li; Hanh T. Hoang; Paul Vulto; Richard J. B. H. N. van den Berg; Herman S. Overkleeft; Jan C.T. Eijkel; Niels R. Tas; Heiko J. van der Linden; Thomas Hankemeier

doi:10.1039/C2LC21011H

Limits of miniaturization: Assessing ITP performance in sub-micron and nanochannels†

Kjeld G. H. Janssen,^ab Jiajie Li,^a Hanh T. Hoang,^c Paul Vulto,^ab Richard J. B. H. N. van den Berg,^d Herman S. Overkleeft,^d Jan C.T. Eijkel,^e Niels R. Tas,^c Heiko J. van der Linden^ab and Thomas Hankemeier*^ab

Author affiliations

* Corresponding authors

^a Department of Analytical Biosciences, Leiden/Amsterdam Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA, The Netherlands
E-mail: hankemeier@lacdr.leidenuniv.nl
Fax: +31 71 5274277
Tel: +31 71 527 4572

^b Netherlands Metabolomics Centre, The Netherlands

^c Department of Transducers Science and Technology, Mesa+ Institute for Nanotechnology, University of Twente, The Netherlands.

^d Department of Bio-Organic Synthesis, Leiden University, The Netherlands.

^e BIOS-lab on a chip group, Mesa+ Institute for Nanotechnology, University of Twente, The Netherlands

Abstract

The feasibility of isotachophoresis in channels of sub micrometer and nanometer dimension is investigated. A sample injection volume of 0.4 pL is focused and separated in a 330 nm deep channel. The sample consists of a biomatrix containing the fluorescently-labeled amino acids glutamate and phenylalanine, 20 attomoles of each. Isotachophoretic focusing is successfully demonstrated in a 50 nm deep channel. Separation of the two amino acids in the 50 nm deep channel however, could not be performed as the maximum applicable voltage was insufficient. This limit is imposed by bubble formation that we contribute to cavitation as a result of the mismatch in electro-osmotic flow, so called electrocavitation. This represents an unexpected limit on the miniaturization of ITP. Nonetheless, we report the smallest isotachophoretic separation and focusing experiment to date, both in terms of controlled sample injection volume and channel height.

Lab on a Chip

Limits of miniaturization: Assessing ITP performance in sub-micron and nanochannels†

Abstract

Supplementary files

Article information

Download Citation

Permissions

Limits of miniaturization: Assessing ITP performance in sub-micron and nanochannels

Social activity

Search articles by author

Spotlight

Advertisements