3D focusing of nanoparticles in microfluidic channels.

Dynamic focusing of particles can be used to centre particles in a fluid stream, ensuring the passage of the particles through a specified detection volume. This paper describes a method for focusing nanoparticles using dielectrophoresis. The method differs from other focusing methods in that it manipulates the particles and not the fluid. Experimental focusing is demonstrated for a range of different particle types, and discussed in terms of the operational limits of the device. Dynamic numerical simulations of the particle motion in the device are presented and compared with the experimental results. The potential of the device for nanoparticle control and manipulation in microfluidic chips is discussed.

[1]  J. Kutter,et al.  Integrating advanced functionality in a microfabricated high-throughput fluorescent-activated cell sorter. , 2003, Lab on a chip.

[2]  J. Michael Ramsey,et al.  Electrokinetic Focusing in Microfabricated Channel Structures , 1997 .

[3]  N. Sundararajan,et al.  Three-dimensional hydrodynamic focusing in polydimethylsiloxane (PDMS) microchannels , 2004, Journal of Microelectromechanical Systems.

[4]  J. Michael Ramsey,et al.  Microchip flow cytometry using electrokinetic focusing. , 1999, Analytical chemistry.

[5]  Torsten Müller,et al.  The influence of higher moments on particle behaviour in dielectrophoretic field cages , 1999 .

[6]  Thomas B. Jones,et al.  Electromechanics of Particles , 1995 .

[7]  S. Quake,et al.  An Integrated Microfabricated Cell Sorter , 2022 .

[8]  A Scherer,et al.  A microfabricated device for sizing and sorting DNA molecules. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[9]  Hywel Morgan,et al.  Numerical solution of the dielectrophoretic and travelling wave forces for interdigitated electrode arrays using the finite element method , 2002 .

[10]  S G Shirley,et al.  Dielectrophoretic sorting of particles and cells in a microsystem. , 1998, Analytical chemistry.

[11]  H. Morgan,et al.  Electrohydrodynamics and dielectrophoresis in microsystems: scaling laws , 2003 .

[12]  S. Quake,et al.  A microfabricated fluorescence-activated cell sorter , 1999, Nature Biotechnology.

[13]  Alan P. Morrison,et al.  Development of a microfluidic device for fluorescence activated cell sorting , 2002 .

[14]  S. Gawad,et al.  Micromachined impedance spectroscopy flow cytometer for cell analysis and particle sizing. , 2001, Lab on a chip.

[15]  Gwo-Bin Lee,et al.  Hydrodynamic Focusing for a Micromachined Flow Cytometer , 2001 .

[16]  D. Holmes,et al.  AC electrokinetic focussing in microchannels: micro- and nanoparticles , 2003 .

[17]  G. Gradl,et al.  A 3-D microelectrode system for handling and caging single cells and particles , 1999 .

[18]  G. Fuhr,et al.  Trapping in AC octode field cages , 2000 .