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Updated: Aug 18, 2026

On-chip Isotachophoresis for Separation of Ions and Purification of Nucleic Acids
Published on: March 2, 2012
Microchip electrophoretic protein separation using electroosmotic flow induced by dynamic sodium dodecyl
Hideya Nagata1, Mari Tabuchi, Ken Hirano
1Department of Molecular and Pharmaceutical Biotechnology, Graduate School of Pharmaceutical Sciences, The University of Tokushima, The 21ST Century COE Program, CREST(JST), Tokushima, Japan. hideya.nagata@aist.go.jp
Abstract:
Separation of sodium dodecyl sulfate (SDS)-protein complexes is difficult on plastic microchips due to protein adsorption onto the wall. In this paper, we elucidated the reasons for the difficulties in separating SDS-protein complexes on plastic microchips, and we then demonstrated an effective method for separating proteins using polymethyl methacrylate (PMMA) microchips. Separation difficulties were found to be dependent on adsorption of SDS onto the hydrophobic surface of the channel, by which cathodic electroosmotic flow (EOF; reversed flow) was generated. Our developed method effectively utilized the reversed flow from this cathodic EOF as a driving force for sample proteins using permanently uncoated but dynamic SDS-coated PMMA microchips. High-speed (6 s) separation of proteins and peptides up to 116 kDa was successfully achieved using this system.
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