Anal. Chem. 2010, 82, 2204–2212
Ac Dielectrophoresis of Tin Oxide Nanobelts Suspended in Ethanol: Manipulation and Visualization Surajit Kumar,*,† Zhengchun Peng,† Heungjoo Shin,‡ Zhong Lin Wang,§ and Peter J. Hesketh† George W. Woodruff School of Mechanical Engineering and School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, and School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology (UNIST), Banyeon-ri 100, Ulsan 689-798, Korea This article presents results of detailed and direct realtime observations of the wide variety of SnO2 nanobelt motions induced by ac dielectrophoresis (DEP) in an innovative microfluidic setup. High ac electric fields were generated on a gold microelectrode (∼20 µm electrode gap) array, patterned on a glass substrate and covered by a ∼10 µm tall polydimethylsiloxane (PDMS) microchannel. Ethanol suspended SnO2 nanobelts were introduced into the microchannel, and the DEP experiments were performed. Negative DEP (repulsion) of the nanobelts was observed in the lowfrequency range (
