Dielectrophoresis continuous

As the number of applications of dielectrophoresis continues to increase, an accurate, comprehensive model becomes a necessary tool for optimal design. Although models exist describing individual dielectrophoretic manipulation techniques (especially for dielectrophoretic trap geometries), few exist for d3mamic systems incorpo-... 

D. E. Raymond, A. Manz, and H. M. Widmer, Continuous Sample Pretreatment Using A Free-Flow Electrophoresis Device Integrated Onto A Sihcon Chip, Analytical Chemistry, vol. 66, no. 18, pp. 2858-2865, Sept 1994. H. Morgan, M. P. Hughes, and N. G. Green, Separation of submicron bioparticles by dielectrophoresis, Biophysical Journal, vol. 77, no. 1, PP-516-525, July 1999. 

B. G. Hawkins, A. E. Smith, Y. A. Syed and B. J. Kirby. Continuous-Flow particle separation by 3D insulative dielectrophoresis using coherently shaped, dc-biased, ac electric fields, Anal. Chem. 79, 7291-7300 (2007). 

ABSTRACT A brief history of the behavior of materials in nonuniform electrical fields is presented, followed by a theory of dielectrophoretic force and the derivation of the general force equation. Attention is paid to the several classes of polarization which lead to the experimental considerations of induced cellular dielectrophoresis. A distinction between batch and continuous methods is discussed, with a focus on a new microtechnique. While dielectrophoresis can induce aggregation of materials, i.e., cells, other orientational applications exist. Cell division, cellular spin resonance, and pulse-fusion of cells form topics appropriate to the realm of high-frequency electrical oscillations and are discussed in the context of living material. 

Cummings EB (2003) Streaming dielectrophoresis for continuous-flow microfluidic devices. IEEE Eng Med Biol Mag 22 75-84... 

Curvature-Induced Dielectrophoresis, Fig. 5 Application of C-iDEP in a serpentine microchaimel to continuous sorting of yeast cells liom 3 pm particles in 1 mM phosphate buffer under an average DC electric field of 10 kV/m The left column shows the snapshot (al) and composite (hi) images of cell/particle focusing at the entrance of the serpentine section the middle column... 

Curvature-Induced Dielectrophoresis, Fig. 6 Application of C-iDEP in a double-spiral microchaimel (a) to continuous sorting of nonfluorescent 5 pm (gray), nonfluorescent 10 pm (dark), and fluorescent 10 pm (bright) particles in 0.1 mM phosphate buffer snapshot image (b) at the entrance of the spiral, composite image... 

Zhu J, Canto RC, Keten G, Vedantam P, Tzeng TJ, Xuan X (2011) Continuous flow separation of particles and cells in a serpentine microchannel via curvature-induced dielectrophoresis. Microfluid Nanofluidics 11 743-752... 

Zhu J, Xuan X (2011) Curvature-induced dielectrophoresis for continuous separation of particles by charge in spiral microchannels. Biomicrofluidics 5 024111... 

Li M, Li SB. Li WH, Wen WJ. Alici G (2013) Continuous manipulation and separation of particles using combined obstacle- and curvature-induced direct current dielectrophoresis. ElectrophOTesis 34 952—960... 

Viefhues M, Eichhom R, Fredrich E, Regtmeier J, Anselmetti D (2012) Continuous and reversible mixing or demixing of nanoparticles by dielectrophoresis. Lab Chip 12 485 94... 

The major application of dielectrophoresis in micro- and nanofluidic systems continues to be the manipulation of particles and cells. Popular applications include particle trapping, dielectrophoretic microsystems, traveling wave dielectrophoresis, and determination of cell dielectric properties. The specific dielectrophoretic techniques used in existing applications are too numerous to cover in this entry. This entry does provide a brief overview of some of the established manipulation techniques. 

Dielectrophoretic techniques have continued to evolve from primitive, macroscale experimentation of Pohl to nanometer-sized particulate manipulation. This evolution is brought in part by the decreasing length scale of microfabrication techniques. As the feature size of fabricated electrodes become smaller and smaller, nanometer dielectrophoresis experimentations and phenomena will continue to unfold. The use of dielectrophoresis as a tool for micro- and nanoassembly has only recently emerged and these applications will continue to be developed. As a nonmechanical and minimally invasive process, dielectrophoresis presents itself for... 

Demmiere, N. (2008). Continuous-Flow Separation of Cells in a Lab-on-a- Chip using Liquid Electrodes" and Multiple-Frequency Dielectrophoresis. Ph.D. thesis, Ecole Polytechnique Federal de Lausanne. 

Kang KW, Kang Y, Xuan X, Li D (2006) Continuous separation of miaroparticles by size with Direct cuirent-dielectrophoresis. Elec-trc horesis 27 694—702... 

He et al. (2013) described a method for the rapid and sensitive detection of Salmonella typhimurium, a foodborne infectious pathogen, in microfluidic channels using positive dielectrophoresis-driven online enrichment and fluorescent NP label. The bacteria were labeled with antibody-conjugated Rubpy-doped fluorescent NPs and enriched by positive dielectrophoresis, then being detected continuously in a microfluidic chip (Figure 3.1) by fluorescence microscopy. The assay of the bacteria at low concentration levels was achieved in less than 2 h with a LOD of 110 cfu mL" in artificially contaminated mineral water samples. 

Continuous dielectrophoresis In expression (3.1.13) for the dielectrophoretic force on an uncharged particle in a nonuniform electrical field, the Clausius-Mossoti function includes Cp and e, which are complex quantities. However, only the real part is useful ... 

Figure 7.3.5. Schematic diagram of continuous dielectrophoresis using a "stream-centered" introduction of the sample cell suspension. (After Pohl (1977).)...

Cells undergoing positive dielectrophoresis move in the radial direction of the merging of the curved rear electrode and the flat front electrode, whereas cells experiencing negative dielectrophoresis move in the opposite direction. Meanwhile, the bulk carrier flow perpendicular to this electrical force carries the cells forward toward the carrier exit. The cells or particles unaffected by the nonuniform electrical field continue to move along the line of original introduction. Thus different cells trace out different trajectories and therefore can be withdrawn at different locations from the stream near the liquid outlet. 

M. W. Wang, Using dielectrophoresis to trap nanobead/stem cell compounds in continuous flow, J. Electrochem. Soc., 2009,156,8, pp. G97-G102. 

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