Effects of dc-dielectrophoretic force on particle trajectories in microchannels

A method of controlling the particle trajectory in a microchannel is demonstrated. The method utilizes the dc-dielectrophoretic (dc-DEP) force created around an insulating hurdle in a microchannel under an applied dc electric field. This method does not require a complicated electrode array which is commonly used in the conventional ac-DEP system. The “proof-of-principle” experiments were carried out using a straight microchannel with a rectangle-shaped hurdle in the middle. The experiments showed that the trajectories of the micron-sized particles can be controlled by the DEP force under electric-field strengths of 5–20kV∕m. To compare with the experimental results, the particle motion was simulated using the Lagrangian tracking method, taking into consideration of the electrophoretic force, the dielectrophoretic force, and the dielectric interaction between the particle and the channel wall. The numerical simulation based on the finite-element method showed a reasonable agreement with the experimental data.

[1]  Hywel Morgan,et al.  AC ELECTROKINETICS: COLLOIDS AND NANOPARTICLES. , 2002 .

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

[3]  Jeremy J. Hawkes,et al.  Force field particle filter, combining ultrasound standing waves and laminar flow , 2001 .

[4]  E. Cummings,et al.  Dielectrophoretic concentration and separation of live and dead bacteria in an array of insulators. , 2004, Analytical chemistry.

[5]  Jonas O Tegenfeldt,et al.  Bacterial chromosome extraction and isolation. , 2002, Lab on a chip.

[6]  J. Santiago.  Electroosmotic flows in microchannels with finite inertial and pressure forces. , 2001, Analytical chemistry.

[7]  T. Johnson,et al.  Imaging of electroosmotic flow in plastic microchannels. , 2001, Analytical chemistry.

[8]  A. Singh,et al.  Dielectrophoresis in microchips containing arrays of insulating posts: theoretical and experimental results. , 2003, Analytical chemistry.

[9]  Maciej Zborowski,et al.  Magnetic cell separation: characterization of magnetophoretic mobility. , 2003, Analytical chemistry.

[10]  E. Cummings,et al.  Insulator‐based dielectrophoresis for the selective concentration and separation of live bacteria in water , 2004, Electrophoresis.

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

[12]  B. Roux,et al.  Rapid intracellular TEA block of the KcsA potassium channel. , 2005, Biophysical journal.

[13]  Chia-Fu Chou,et al.  Electrodeless dielectrophoresis of single- and double-stranded DNA. , 2002, Biophysical journal.

[14]  Masao Washizu.  Electrostatic manipulation of biological objects , 1990 .

[15]  Ronald Pethig,et al.  Dielectrophoretic characterization and separation of micro-organisms , 1994 .

[16]  Anup K. Singh,et al.  Dielectrophoretic trapping without embedded electrodes , 2000, SPIE MOEMS-MEMS.

[17]  Robert H. Davis,et al.  Particle transport in Poiseuille flow in narrow channels , 2005 .

[18]  Paul C. H. Li,et al.  Transport, manipulation, and reaction of biological cells on-chip using electrokinetic effects. , 1997, Analytical chemistry.

[19]  J. Israelachvili.  Intermolecular and surface forces , 1985 .

[20]  F. Zenhausern,et al.  Electrodeless dielectrophoresis for micro total analysis systems , 2003, IEEE Engineering in Medicine and Biology Magazine.

[21]  H. Morgan,et al.  Ac electrokinetics: a review of forces in microelectrode structures , 1998 .

[22]  D. Grier.  A revolution in optical manipulation , 2003, Nature.

[23]  S. K. Griffiths,et al.  Conditions for similitude between the fluid velocity and electric field in electroosmotic flow , 1999, Analytical chemistry.

[24]  R. Pethig,et al.  Separation of viable and non-viable yeast using dielectrophoresis. , 1994, Journal of biotechnology.

[25]  P. Gascoyne,et al.  Particle separation by dielectrophoresis , 2002, Electrophoresis.